Officers located a man the agency identified as Mario Christopher Washington, 42, of Berkeley. He was arrested on a charge of suspicion of assault with a deadly weapon and booked into the Alameda County North Jail in downtown Oakland.
Police say Washington's first alleged attack occurred at 7:31 p.m. last Thursday evening at the Bay Fair Station in San Leandro. The police narrative of the event read:
A male victim was seated on a train when a male suspect (black male, late 30s, 6 feet, muscular, grey shirt, tan shorts, black shoes) hit him in the head with an unknown metal object. The suspect also punched and kicked the victim before fleeing the train and running out of the station. According to the victim and witnesses, the attack was unprovoked. The suspect was not located. The victim was treated for a laceration to his head and transported to the hospital via ambulance with non-life threatening injuries.
BART police identified the weapon used in the Thursday attack as a bolt cutter.
The second attack occurred Saturday evening on an East Bay train bound for San Francisco, police said. Here's the narrative of that incident:
On August 5, 2017, at approximately 1930 hours, the same suspect was on a San Francisco Bound train approaching Embarcadero Station. The suspect approached a man on the train and struck the man two times in the face with a closed fist. The victim does not know the suspect. The suspect fled the scene. The victim received medical treatment at the scene for non-life threatening injuries.
BART spokesman Jim Allison said the agency called the early-morning press conference because of concerns about possible further assaults by the suspect.
"The detective who was working the Thursday case saw enough similarities in the Saturday case that he was afraid he was going to attack again," Allison said. That prompted an overnight effort to publicize images captured on train cars near the time of the two assaults.
Milpitas police reported arresting Washington in January on a charge of strong-arm robbery and noted that he was wanted under a felony warrant in Oakland for allegedly violating the terms of an earlier release from state prison.