(CNN) — Protests in Missouri around the death of an unarmed teen turned violent late Sunday.
A gas station was looted, and police called for additional units to back up officers already on the street, said Brian Schellman, spokesman with the St. Louis County Police Department.
Video from the scene showed police in riot gear. No injuries were immediately reported.
“They are sending in more officers to try and get the situation under control,” Schellman said.
Ferguson Police Chief Thomas Jackson said that at least 20 police cars were damaged and that the use of tear gas was a high possibility.
A friend and witnesses say Missouri teen Michael Brown was unarmed and had his hands in the air when a Ferguson police officer shot and killed him, but that account is in dispute.
“The genesis of this was a physical confrontation,” Jon Belmar, chief of the St. Louis County Police Department, said at a Sunday news conference.
The officer tried to leave his vehicle just before the shooting on Saturday afternoon, but Brown pushed him back into the car, “where he physically assaulted the police officer” and struggled over the officer’s weapon, Belmar said.
A shot was fired inside the police car, and Brown was eventually shot about 35 feet away from the vehicle, Belmar said, adding few details because he didn’t want to “prejudice” the case.
All shell casings collected at the scene were from the officer’s weapon, Belmar said. He further said the medical examiner would issue a ruling on how many times Brown was shot, but “it was more than just a couple.”
The account was in stark contrast to those of witnesses who said Brown did nothing to instigate the shooting and appeared to be surrendering when he was killed.