Man allegedly masturbating on BART placed under citizen’s arrest

Riders at the 19th Street BART station in Oakland, Calif. on Saturday, Aug. 1, 2015. Riders at the 19th Street BART station in Oakland, Calif. on Saturday, Aug. 1, 2015. Photo: Paul Chinn, The Chronicle Buy photo Photo: Paul Chinn, The Chronicle Image 1 of / 23 Caption Close Man allegedly masturbating on BART placed under citizen’s arrest 1 / 23 Back to Gallery

A man allegedly masturbating on a BART train was placed under citizen’s arrest in Oakland early Thursday by a fed-up woman who caught him in the act and contacted police, officials said.

The 53-year-old Pittsburg man was allegedly masturbating on a Pittsburg-Bay Point train about 4:40 a.m. when a fellow passenger put him under citizens arrest at the 19th Street Station in Oakland, getting the attention of police and telling them she would act as a witness to the incident, according to BART police.

The woman flagged down police who were conducting a patrol check of the train, and the man was arrested by the officers and booked into Glenn Dyer Jail in Oakland on suspicion of indecent exposure about 7:20 a.m., police said.

His bail has been set at $10,000, and he’s scheduled to be arraigned on Friday at the Gale-Schenone Hall of Justice in Pleasanton, according to county records.

Filipa Ioannou is a San Francisco Chronicle staff writer. Email: fioannou@sfchronicle.com Twitter: @obioannoukenobi