A San Francisco man has been arrested on suspicion of attempted murder in connection with Saturday’s stabbing at the Oakland Coliseum BART station, a transit agency spokeswoman said.

BART Stabbing Suspect Booking Photo

Robert Dolph. (Photo via BART)

Robert Dolph, 32, was arrested and booked into Santa Rita Jail in Dublin on two counts of attempted murder. According to BART spokeswoman Alicia Trost, Dolph allegedly admitted his involvement in the crime during an interview with investigators.

At a Sunday afternoon news conference, BART Deputy Police Chief Lance Haight said: “The attack appears to be entirely unprovoked and there’s an unknown motive,”

Haight said a woman in her 60s and her brother in his 50s got on at the South San Francisco BART station and disembarked at the Coliseum BART station Saturday, at 2:52 pm.

“While they were on the train, they noticed this man get on the train who was pacing back and forth muttering to himself and shouting things out,” Haight said. “They became alarmed by his behavior so when the train arrived at the Coliseum BART station, they tried to elude him as fast as they could. They walked downstairs and he started following them and was blocking the fare gates so they couldn’t exit.”

As the siblings finally did exit at the attendant’s booth, he attacked them with a large fixed blade knife, Haight said.

Both victims were stabbed in the head. The male victim was also stabbed in the chest. He is in critical condition with knife wounds to his head. His sister had less serious injuries and her condition was described as fair.

A good Samaritan came to the rescue, wrestling the knife from the suspect and holding him until law enforcement officers appeared two minutes later, according to Trost.

A second good Samaritan helped hold the suspect down as he was handcuffed. The knife was recovered at the scene.

“The swift response by the station agent and police as well as the intervention by the good Samaritans were all critical to ending the attack and apprehending the suspect,” Trost said in a statement.

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