BART police investigating another robbery at Oakland Coliseum station

OAKLAND, Calif. (KGO) -- BART police are investigating another robbery on its system at Oakland's Coliseum station.

They say at least 10 teenagers grabbed a woman's iPhone as they got off a train Friday night. A good Samaritan chased the teens down and got the phone back.

RELATED: Dozens of teens rush Oakland BART train, rob passengers

BART police caught the suspects but released the teens to their parents when witnesses couldn't be sure who exactly had taken the phone.

This incident follows a high-profile attack in April, when some teens robbed and beat riders at the station.

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