And it has happened again, during Halloween festivities in the South Korean capital Seoul, where a crowd pushed forward, the narrow street they were on acting as a vice, leaving more than 140 people dead and 150 more injured.

The risk of such tragic accidents, which receded when venues closed and people stayed home due to the COVID-19 pandemic, has returned.

To be sure, most events where large crowds gather happen without injury or death, with fans coming and going without incident. But those that went horribly wrong shared some common traits. Here is a look at why that happens:

How do people die at these events?

While movies that show crowds desperately try to flee suggest getting trampled might be the cause of most of the deaths, the reality is most people who die in a crowd surge are suffocated.

What cant be seen are forces so strong that they can bend steel. That means something as simple as drawing breath becomes impossible. People die standing up and those who fall die because the bodies on top of them exert such pressure that breathing becomes impossible.

As people struggle to get up, arms and legs get twisted together. Blood supply starts to be reduced to the brain, G. Keith Still, a visiting professor of crowd science at the University of Suffolk in England, told NPR after the Astroworld crowd surge in Houston last November. It takes 30 seconds before you lose consciousness, and around about six minutes, youre into compressive or restrictive asphyxia. Thats a generally the attributed cause of death not crushing, but suffocation.

What is the experience of being swept up in a crush of people like?

Survivors tell stories of gasping for breath, being pushed deeper under what feels like an avalanche of flesh as others, desperate to escape, climb over them. Of being pinned against doors that wont open and fences that wont give.

Survivors described being gradually compressed, unable to move, their heads locked between arms and shoulders faces gasping in panic, according to a report after a human crush in 1989 at the Hillsborough soccer stadium in Sheffield, England, led to the death of nearly 100 Liverpool fans. They were aware that people were dying and they were helpless to save themselves.

What triggers such events?

At a Chicago nightclub in 2003, a crowd surge began after security guards used pepper spray to break up a fight. Twenty-one people died in the resulting crowd surge. And this month in Indonesia, 131 people were killed when tear gas was fired into a half-locked stadium, triggering a crush at the exits.

In Nepal in 1988, it was a sudden downpour that sent soccer fans rushing toward locked stadium exits, leading to the deaths of 93 fans. In the latest incident in South Korea, some news outlets reported that the crush occurred after a large number of people rushed to a bar after hearing that an unidentified celebrity was there.

But Still, the British professor who has testified as an expert witness in court cases involving crowds, pointed to a variation of the age-old example of someone shouting Fire in a crowded movie theater. He told the AP last year that what lights the fuse of such a rush for safety in the U.S., more than in any other country, is the sound of someone shouting: He has a gun!

What role did the pandemic play?

Stadiums are filling up again. During the pandemic, as games went forward, teams took some creative steps to make things look somewhat normal. Cardboard figures of fans were placed in some of the seats and crowd noise was piped in  a sports version of a comedy show laugh track.

Now, though, the crowds are back, and the danger has returned.

As soon as you add people into the mix, there will always be a risk, Steve Allen of Crowd Safety, a U.K.-based consultancy engaged in major events around the world, told the AP in 2021.

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The proposed agreement, which includes performance reporting requirements and provisions laying out a degree of construction cost sharing, is still subject to final approval by the State Corporation Commission.

Attorney General Jason Miyares, a Republican whose office represents the interests of consumers in utility regulation proceedings, said the agreement would provide first-of-its-kind protections for ratepayers while ensuring the 176-turbine project with an estimated $9.8 billion capital cost moves forward in a fiscally responsible way.

I am pleased that we have achieved consumer protections never seen before in modern Virginia history, Miyares said in a statement. For the first time Dominion has significant skin in the game to ensure that the project is delivered on budget. Should the project run materially over budget, it will come out of Dominions pocket, not consumers, he said.

Dominion filed its application to build and recover the costs of the project with the State Corporation Commission nearly a year ago. That kicked off a lengthy process before the regulatory agency, one that has included voluminous filings and an evidentiary hearing in May.

The commission in August signed off on the project, but it included a consumer protection provision a performance guarantee that Dominion strenuously objected to, saying it would kill the project.

The parties to Fridays proposal said they had conferred since then and reached the terms of the proposed agreement. It calls for a cost-sharing arrangement for any overruns beyond the estimated $9.8 billion price tag. The company would cover 50% of construction costs between the range of $10.3-$11.3 billion and 100% of costs between $11.3-$13.7 billion. If construction costs were to exceed $13.7 billion, the issue would go back to the commission.

The proposal would not require the company to guarantee certain energy production levels, like the SCC had initially ordered. Rather, Dominion will have to report average net capacity factors annually and provide a detailed explanation of the factors contributing to any deficiency. Capacity factor is a measure of how often a generating facility runs during a period of time.

Richmond-based Dominion said in a news release that the deal would provide significant customer benefits.

I appreciate the thoughtful effort of all parties in reaching a constructive agreement to allow the project to continue moving forward, said Bob Blue, Dominions chair, president and and chief executive officer.

Also parties to the agreement are Walmart, Virginias largest private employer, and two conservation groups: Appalachian Voices and the Southern Environmental Law Center.

Will Cleveland, an attorney for SELC, emphasized in a statement that the primary issue in the case was never about offshore winds value but the risks created by the ownership structure.

No other offshore wind project under development in the U.S. is funded by captive ratepayers, and no other project has a monopoly utility owner acting as its own general contractor, the law center said.

The project, which will be located about 27 miles off the coast of Virginia Beach, has drawn broad support from local officials, policymakers, business groups and trade unions, who say it will help fight climate change and create jobs.

The company already has a two-turbine pilot project up and running. The 2.6-gigawatt, utility-scale projects schedule calls for construction to be complete in late 2026. Dominion expects the project to generate enough clean energy to power up to 660,000 homes.

Clean Virginia, an environmental and rate reform advocacy group that is a party to the proceeding, did not oppose the agreement, which it said in a statement represented a vast improvement for consumers.

Absent pressure from environmental advocates, the Office of the Attorney General, regulatory staff, and Walmart, Dominion would have proceeded with one of the most expensive energy projects to date in Virginia with few consumer protections and would have faced little performance expectations to actually generate consistent clean energy, Laura Gonzalez, the groups energy policy manager, said in a statement.

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Prime Minister Mateusz Morawiecki said late Friday on Twitter that Poland would use the reliable, safe technology of the Westinghouse Electric Company for the plant in Pomerania province near the Baltic Sea coast. The exact location remains to be identified.

A strong Poland-U.S. alliance guarantees the success of our joint initiatives, Morawiecki said.

Poland is planning to spend $40 billion to build two nuclear power plants with three reactors each, the last one to be launched in 2043. The deal with the U.S. and Westinghouse is for the first three reactors of the Pomerania plant, which officials saying should start producing electricity in 2033.

Poland has planned for decades to build a nuclear power plant to replace its aging coal-fired plants in a country with some of the worst air pollution in Europe. Construction of a Soviet-technology nuclear plant began in the early 1980s, when Poland was in the East Bloc.

Protests by residents and environmentalists, the 1986 disaster at the Chernobyl nuclear power plant in Ukraine and budget shortages led to the scrapping of the project.

Russias invasion of Ukraine this year and its use of energy to put economic and political pressure on European nations have added urgency to Polands search for alternative energy sources.

Polish government spokesman Piotr Mueller said Saturday that the government would adopt a decision at its meeting Wednesday, which will launch environmental approval and investment procedures.

Mueller said the nuclear plant in northern Poland would require improving infrastructure in the area, including roads.

U.S. Energy Secretary Jennifer Granholm said the project would create or sustain more than 100,000 jobs for American workers.

This is a HUGE step in strengthening our relationship with Poland to create energy security for future generations to come, Granholm said.

This announcement also sends a clear message to Russia: We will not let them weaponize energy any longer, Granholm said. The West will stand together against this unprovoked aggression, while also diversifying energy supply chains and bolstering climate cooperation.

Poland had also considered offers from France and South Korea. Poland State Assets Minister Jacek Sasin suggested there could still be a role for South Korea in the project and more talks are scheduled in Seoul next week.

Westinghouse has sued in federal court to block a potential deal for competitor Korea Hydro and Nuclear Power to sell reactors to Poland.

The United States is one of the most important allies of NATO-member Poland. After Russias invasion of Ukraine in February, the U.S. increased its military presence in the country, creating a permanent presence for the first time, and using Poland as a hub for sending weapons to Ukraine.

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Its affirmative action program, using race among many factors to build a diverse student body, is similar to plans in place at other selective public and private institutions.

But a Supreme Court that has twice blessed race-conscious college admissions programs in the past 19 years now seems poised to restrict their use or outlaw them altogether.

The case, following the overturning of the nearly 50-year precedent of Roe v. Wade in June, offers another test of whether the court now dominated by conservatives will move the nations policies to the right on another of its most contentious cultural issues.

The court is hearing two cases Monday, involving UNC and Harvard, the nations oldest public and private universities, respectively.

The challengers to the universities programs have lost at every step as lower courts have rejected their claims that the schools discriminate against white and Asian American applicants.

But Students for Fair Representation, the creation of conservative activist Ed Blum, has always pointed toward the nations highest court, more conservative now that former President Donald Trumps three nominees are among the nine justices, as the best forum to roll back more than 40 years of court rulings that allow race to be one factor among many in admissions.

North Carolinas flagship university in Chapel Hill is a curious place to make that case.

The first Black students didnt arrive until 1951, and then only under court order. Into the 1980s, students reported they were subjected to racial slurs and astonishing displays of insensitivity, including being asked to do laundry by a white classmate, according to an account by historian David Cecelski that is included in court documents.

Even now, U.S. District Judge Loretta Biggs noted in her 2021 decision upholding the universitys program, underrepresented minorities win admission to UNC at lower rates than do white and Asian American applicants and minority students at the University still report being confronted with racial epithets, as well as feeling isolated, ostracized, stereotyped and viewed as tokens in a number of University spaces.

Defending its program, North Carolina wrote in its main brief to the Supreme Court that the school continues to have much work to do.

On a recent, brilliant fall day in Chapel Hill, students talked about what they see as the benefits and drawbacks of affirmative action in college admissions.

Christina Huang, an 18-year-old freshman from West Milford, New Jersey, who is co-director of UNC for Affirmative Action, said diversity on campus enriches the learning environment for all students, even outside the classroom.

I think theres a negative connotation of affirmative action and this idea that its a quota and its hurting Asian Americans, said Huang, a first-generation college student who is studying political science. But culture plays such a big role, especially on UNCs campus, because you walk around and theres culture everywhere. Theres people dressed up in traditional clothes, fashion shows, people dancing to their different types of music, even the foods we eat its so meaningful. Youd lose so much if we were not to make sure we have that diversity.

Students now picnic under the billowing trees in McCorkle Place where the Confederate statue Silent Sam stood for more than 100 years until protesters toppled it in 2018.

Joy Jiang, a 19-year-old sophomore from Harrisburg, North Carolina, and co-director of the affirmative action group, said recent racial tensions on campus that she described as a backlash after the statue came down, have scared away some students of color from vocalizing their support for affirmative action.

Jacob James, 20, of Robersonville, North Carolina, recognized the value of diversity. Diversity on college campuses is good, but it shouldnt come at the expense of fairness, said James, the chairman of UNC College Republicans. Affirmative action, he said, unfairly disadvantages some individuals over other individuals based on race.

James comment meshes with the main point made by Blums group, that the Constitution forbids any consideration of race. Students for Fair Admission said it draws support from the seminal case of Brown v. Board of Education, the 1954 decision that paved the way for the desegregation of the nations public schools.

The group told the justices that Brown rejected many of the arguments UNC is making. It argues that racial classifications make everyone better off. It warns that universities cannot discard race quite yet. And it contends that the legality of its practices should be decided by North Carolinians, not this Court. The segregationists agreed, according to the groups final Supreme Court brief.

Students for Fair Representation also makes repeated use of the June decision to overturn Roe v. Wades constitutional protection for abortion to bolster its arguments that the court should jettison its affirmative action precedents.

The abortion decision in Dobbs v. Jackson Womens Health Organization strongly suggests the court would be willing to impose an all-out ban on considering race in college admissions, said Paulette Granberry Russell, president of the National Association of Diversity Officers in Higher Education.

The implications extend well beyond UNC and Harvard. It may very well result in a different outcome than what we have seen in the Bakke case, the Grutter case in 2003, the Fisher cases, Granberry Russell said, citing the courts earlier college admissions cases.

Blum, who has worked for years to rid college admissions of racial considerations, also was behind the ultimately losing lawsuit on behalf of Abigail Fisher, a white woman who claimed discrimination explained her rejection by the University of Texas.

That case was decided only six years ago, but the makeup of the court has changed significantly since then, with the addition of the three Trump appointees and Justice Ketanji Brown Jackson, the courts first Black woman.

Jackson is sitting out the Harvard case because she was on an advisory board until recently. But she is taking part in the North Carolina case, which strongly suggests the court would use that case if it ends up making a major pronouncement on affirmative action.

Every U.S. college and university the justices attended, save one, is urging the court to preserve race-conscious admissions.

Four justices attended law school at Harvard, and two were undergraduates there. Yale, Princeton, Columbia, Notre Dame and Holy Cross also have joined briefs in defense of Harvards and UNCs admissions plans.

Only Justice Amy Coney Barretts undergraduate alma mater, Rhodes College, in Memphis, Tennessee, is not involved in the cases.

Nine states already prohibit any consideration of race in admissions to public colleges and universities: Arizona, California, Florida, Georgia, Michigan, Nebraska, New Hampshire, Oklahoma and Washington.

In California, the same electorate that gave President Joe Biden a 5-million-vote margin over Trump in 2020 handily rejected a proposal to revive affirmative action.

Public opinion on the topic varies depending on how the question is asked. A Gallup Poll from 2021 found 62% of Americans in favor of affirmative action programs for racial minorities. But in a Pew Research Center survey in March, 74% of Americans, including majorities of Black and Latino respondents, said race and ethnicity should not factor into college admissions.

A decision in the affirmative action cases is not expected before late spring.

___

Sherman reported from Washington. AP Education Writer Collin Binkley in Washington contributed to this report.