About two dozen people were injured at Coors Field Wednesday night after a crowded escalator near the C Gate apparently malfunctioned and suddenly started to speed up, sending people crashing into one another and forcing others to tumble down, authorities said.

"It's like it had no brakes and everybody was just piling up at the end of it," said Cherri Brownfield, who was on the escalator when it sped up. "People were just falling on each other."

One eyewitness said that people were screaming and sliding down "like an avalanche." A vendor said he saw people's heads hitting each other and people's bodies banging against the escalator.

Between 20 and 23 people were taken by ambulance to local hospitals, many of them suffering from broken bones, bruises and cuts, said Denver Assistant Fire Chief Larry Trujillo. Luckily, none of the injuries were considered critical or life-threatening, he said.

Authorities are looking into what could have caused the escalator at Section 122 to suddenly accelerate. The long escalator is on the side of 1st base and connects the upper concourse to ground level.

More than 47,000 people packed Coors Field Wednesday night for the Colorado Rockies game against the Arizona Diamondbacks and for the post-game fireworks show.