Bay Area Rapid Transit police are beefing up patrols at Oakland stations after dozens of juveniles terrorized riders Saturday night when they invaded the Coliseum Station and commandeered at least one train car, forcing passengers to hand over bags and cell phones and leaving at least two with head injuries.

The incident occurred around 9:30 p.m. Saturday. Witnesses told police that 40 to 60 juveniles flooded the station, jumped the fare gates and rushed to the second-story train platform. Some of the robbers apparently held open the doors of a Dublin-bound train car while others streamed inside, confronting and robbing and in some cases beating riders.

“I’ve been there 24 years and this is the first time I’ve heard of anything like this happening,” said Keith Garcia, a BART police officer and union president.

Alicia Trost, a BART spokeswoman, told SFGate Monday that seven people were robbed — with the victims losing a purse, a duffel bag and five phones. Six people were robbed inside the train car, with a seventh confronted on the platform, she said. Police received no reports of guns or other weapons being brandished.

A police summary prepared after the incident said that at least two victims suffered injuries to the face or head that required medical attention.