A District teenager who allegedly sexually assaulted a woman on a Metro station platform and an Orange Line train has been arrested, officials said.

Michael Levaughn Williams, 19, is accused of approaching a woman on a platform at the L'Enfant Plaza Metro Station on Jan. 29 and groping her, Metro officials said. The victim was then able to break free.

The victim told police that the same man who attacked her on Jan. 29 also approached her on an Orange Line train on Feb. 2 and groped her, officials said. A bystander intervened, contacted the train operator and requested police assistance, but Williams ran off the train at the Landover station before police arrived.

After the second assault, the victim was shown an array of photos and identified Williams as her attacker. Metro Transit Police had taken Williams' picture after they had stopped him in connection with an unrelated harassment call, Metro spokesman Dan Stessel said.

Williams was stopped by Metro Transit Police on Thursday at the L'Enfant Plaza station and arrested on a misdemeanor sexual abuse charge in connection with the Jan. 29 incident. Charges are pending in connection with the Feb. 2 incident, officials said.