STILLWATER, Okla. — After an annual football game they call Bedlam, thousands of Oklahoma State fans jumped, ran and pushed their way onto the field in joy. The Cowboys had just taken apart the Oklahoma Sooners, their bitter and often more successful rivals. The Cowboys’ first national championship suddenly seemed within reach.

But fans were pressing toward the field, which is separated from the stands by a nine-foot brick wall. Some students jumped down, others were pushed. The crowd pulled down the goal posts, and in the 45 minutes or more it took police to restore order Saturday night, some fans were trampled as the crowd struggled to reach the exits.

At least 12 people were injured, including one who was airlifted to a hospital, in the chaos on the field after an emotional win in the heart of football country.

“Thousands of people stormed the field. You couldn’t move there were so many people,” said Michael Authement, who heads the command post at emergency medical provider LifeNet EMS. “It was a nasty deal.”

The field is not designed to allow huge crowds to get in or out. Narrow staircases on the north, south and west ends are the only ways to reach the field from the seating areas. There are two ramps on the east end, which has no seats.

To get back off the field, fans were crunched together and pushing to get their way to the exits.

The public address announcer had warned fans not to storm the field, but “we just laughed,” said Alex Lillibridge, a 19-year-old freshman from Belton, Texas. Fans started jumping the wall in the last seconds of Oklahoma State’s 44-10 win, and Lillibridge said that soon after he followed.

Some people said they were forced to jump because of the crush of fans.

“A girl pushed me over the wall,” said 21-year-old Jennifer Payne, a junior from Stillwater. “Luckily, I didn’t get injured, but I didn’t have control of when I jumped off the wall. You just moved with the crowd.”

— The Associated Press