ACC Commissioner John Swofford makes the announcement that the ACC tournament has been cancelled due to the coronavirus. (2:03)

The Power 5 leagues -- the ACC, Big Ten, Big 12, SEC and Pac-12 -- canceled their men's basketball conference tournaments Thursday, with several leagues going as far as to indefinitely postpone all athletic events amid the coronavirus pandemic.

Also announcing that their tournaments would not be played were the American, Atlantic 10, Conference USA, MAC, America East, Big Sky, MAAC, MEAC and WAC.

The Big East briefly continued its tournament, as St. John's and Creighton played the first half of their quarterfinal matchup, before the conference announced its cancellation and ended that game at halftime.

Later Thursday, the ACC announced that all athletic-related activities, including NCAA championships, were suspended until further notice.

The Pac-12, American, Mountain West and Big West also announced that all conference sporting events would be canceled until further notice. The Big 12 said other conference championships, including women's basketball, gymnastics and equestrian events, were off through April 15. The SEC said it is suspending all competitions on home campuses until March 30.

The Big Ten, following a move first taken by the Ivy League on Wednesday, also announced there would be no more spring sport competitions this year.

"We made the decision not based upon the financial impact of the conference," Big Ten commissioner Kevin Warren told ESPN's Heather Dinich. "We wanted to do what was right."

SEC commissioner Greg Sankey said the recommendation from the NCAA's COVID-19 panel against holding sporting events open to the public "literally changed the game for us."

The Big 12, MAC, MEAC, Missouri Valley and America East women's basketball tournaments were also among the cancellations.

The MEAC continued to finish the Delaware State-Morgan State women's basketball quarterfinal, which was in the fourth quarter when the conference's decision was announced. Morgan State won 64-63 in what appears to be the final NCAA basketball game, men's or women's, of the 2019-20 season.

Within minutes of one another, the five most high-profile conferences in college sports announced that the remainder of their tournaments would not be played. All were preparing to play games in large arenas across the country, but with few people in the buildings.

"We believe that it's the right decision to make at this particular point in time," ACC commissioner John Swofford said. "You can ask, 'Why was it not made sooner?' It's a fair question. The answer is that it's an extraordinarily fluid situation with information coming to us that changes. I used to say by the week, then I say by the day, and now I say by the hour. So hopefully we're doing the right thing in the context of this great country of ours and in the context of intercollegiate sports."

ACC top seed Florida State was awarded the league's championship trophy in an odd ceremony with Swofford in a mostly empty arena.

Following the conference tournament announcements, Kansas and Duke revealed Thursday that all athletic travel has been canceled indefinitely.

Blue Devils coach Mike Krzyzewski said in a statement that his team "emphatically" supports the decision. Kansas, the No. 1 team in the country and the presumptive top overall seed, followed Duke in announcing a suspension of athletic travel.

In Kansas City, Missouri, Texas and Texas Tech were going through pregame warm-ups and the handful of close family and friends were already in the stands when the teams were pulled off the court 40 minutes before tipoff.

"I think this is emblematic of how our country will be responding to a very unusual set of circumstances," Big 12 commissioner Bob Bowlsby said. "I feel good that we made the right decision for the right reasons."

Addressing the Big Ten's decision to cancel, Michigan coach Juwan Howard said in a statement that "some things are bigger than basketball."

On Wednesday, the NCAA announced that the men's and women's basketball tournaments would be played without fans in attendance. The NCAA said only essential staff and limited family members would be allowed to attend the games.

The decisions are part of ongoing actions to prevent the spread of the coronavirus, which was labeled a pandemic Wednesday by the World Health Organization.

For most people, the coronavirus is believed to cause only mild or moderate symptoms, such as fever and cough. For some, especially older adults and people with existing health problems, it can cause more severe illness, including pneumonia.

The vast majority of people recover from the virus. According to the WHO, people with mild illness recover in about two weeks, while those with more severe illness might take three to six weeks to recover. Social distancing, which includes canceling events that draw large crowds, is designed to slow the transmission of the disease.

The Associated Press contributed to this report.