The NFL postponed the Buffalo Bills game against the Cincinatti Bengals a little more than an hour after Bills safety Damar Hamlin collapsed on the field during the first quarter after making a tackle.

The incident shocked viewers and television audiences as Hamlin was given CPR on the field and was taken away in an ambulance as confused and worried football fans watched. It is unclear what brought on the collapse, but here is what is known so far:

1. The 24-year-old had made a play, taking down Bengals wide receiver Tee Higgins at the 5:58 point in the game’s first quarter. Higgins had caught a 13-yard pass from quarterback Joe Burrow and in attempting his run, apparently hit Hamlin on the chest with his helmet. The two went down and Hamlin got up, but a few seconds later fell down and lay on the field without moving. The Bills later posted on social media that Hamlin suffered a cardiac arrest, but his heartbeat was restored before he was taken off the field.

2. Paramedics came to the field to administer CPR and did so for about 10 minutes, then took him away from Paycor Stadium for hospitalization. Members of both teams wept, hugged and prayed as Hamlin's family came to the field. Burrow and Bills quarterback Josh Allen hugged one another. Fans in the stands waited to see if the game would continue. Meanwhile Hamlin was listed in critical condition at University of Cincinnati Medical Center. A journalist from Cincinnati’s WXIX tweeted that he had been told Hamlin had a pulse but was not breathing on his own.

3. The game was suspended while a decision was made, but both coaches decided that game play could not continued and players were called off the field.The NFL postponed the week 17 game, which was one in which the Bengals (11-4) were vying against the Bills (12-3) seeking a path to the top seed in the AFC playoffs. The Bengals were winning 7-3. However, after Hamlin was taken off the field, the mood became increasingly serious and there was little concern for game play and far more concern for the defenseman. The league has not announced a new day and time for the continuation of the game.

4. Hamlin, in his second NFL season out of Pittsburgh and a 2021 6th round draft pick;, started in 14 games this season; made 63 solo tackles, the second most on the Bills behind linebacker Matt Milano. At Pitt, Hamlin was a four-year standout on the defense and made nearly 300 career tackles before being drafted. It is unclear if he has had any health problems that affected his play.

5. Fans, emotional and seeking a way to support Hamlin and his family, poured funds into his charity, the Chasing M’s Foundation, which was started before he entered the NFL in 2021. As of Tuesday afternoon (Jan. 3), the foundation’s GoFundMe page had raised more than $4 million, far more than the initial goal of $2,500. The funds were intended to benefit children in Hamlin’s hometown of McKees Rock’s, Pa. On Christmas day, he left a message on Instagram encouraging people to give.

6. Hamlin's family released a statement thanking all of his supporters for their encouragement and prayers. They promised to update the public as soon as there are new developments. 

Editor's Note: This story has been updated.