Two people had their phones yanked from their hands. BART police were able to detain the group, and arrested a 14-year-old.
Rusty Stapp of Dublin wasn't surprised to hear of the theft. He's suing BART after a group of teenagers took over his train in April. They attacked him and robbed him, his wife, and daughter.
"My big worry is at some point there's going to be a worse incident than what we had," said Stapp. "Rather than just a beating or a robbery, someone is going to pull a gun, or someone is going to pull a knife."
Stapp wants to see more BART police at high crime stations and on trains. He also wants officials to crack down on fare evaders.
This is just the latest in a string of robberies and attacks at BART stations.
Thursday, a man at Station was punched in the head and robbed while buying his ticket.
Friday, a passenger was knocked to the ground of his train in an attempted cell phone theft.
Later that night, a phone was snatched from a passenger at Union City Station. Another cell phone was taken from the hands of a victim walking down the steps to the street station in San Francisco.
BART has not released any video of the incidents. The transit company launched an awareness campaign this summer.
BART says they make regular safety announcements and posted signs in trains urging riders to protect phones.