Horrifying video shows crowded escalator speed out of control, injuring at least 20

A terrifying escalator accident caught on camera at Repubblica metro station in Rome, Italy, left nearly two dozen people injured on Tuesday, Reuters reports.

The majority of those involved are believed to be Russian soccer fans who were on their way to watch CSKA Moscow face off against AS Roma in Tuesday's Champions League game.

Cellphone footage of the incident shows dozens of fans traveling down the malfunctioning escalator, which had suddenly sped out of control, causing passengers to become crushed at the bottom of the fast-moving steps.

Local media reports that the incident spurred panic at the metro station, with many onlookers fearing there had been a terror attack. At least three people suffered serious injuries and one man had to have part of his foot amputated.

First responders shared an image of the mangled escalator steps on Twitter, showing the severity of the damage.

Mayor of Rome Virginia Raggi told reporters that local transport authority had opened an investigation into what caused the accident.

"From what witnesses have said, it seems that some fans were jumping and dancing on the stairs," Raggi said.