College basketball fans will be barred from the March Madness tournament to prevent the possible spread of coronavirus, with games played inside mostly empty arenas, including the Final Four tournament and championship games in April.
Only "essential staff and limited family attendance" will be permitted, according to a statement from NCAA president Mark Emmert.
The decision impacts all upcoming championship events in the Division I men's and women's basketball tournaments. The first games are set to begin 17 March.
He said: "While I understand how disappointing this is for all fans of our sports, my decision is based on the current understanding of how Covid-19 is progressing."
"The decision is in the best interest of public health, including that of coaches, administrators, fans and, most importantly, our student-athletes", he said.
Sixty-eight teams are set to compete in the tournament, which advances to a Final Four tournament and championship game in April.
NBA and MLB fans also could be absent at upcoming games as the leagues heed public health officials' advice to avoid mass gatherings in the wake of the outbreak, which has surpassed 1,000 patients in the US, including at least 33 deaths.
On Thursday, California's Golden State Warriors and the Brooklyn Nets will play to an empty stadium, after San Francisco Mayor London Breed banned all gatherings of 1,000 or more people for the next two weeks.
The Seattle Mariners baseball team has moved its games out of the area for the month, after Washington state Governor Jay Inslee banned gatherings of 250 people or more.
On Wednesday, the World Health Organization declared the global spread of a coronavirus as a pandemic, its first such declaration in more than a decade during the H1N1 "swine flu" outbreak.
More than 1,000 people in the US have been infected with the flu-like respiratory illness, leading to nearly 40 deaths. The global death toll has topped 4,000 as the virus has spread to more than 100 countries.
