OAKLAND (CBS SF) — Amid an ongoing epidemic of cellphone theft on BART, four people had their phones stolen in separate incidents and one man was knocked to the floor of a train in an attempted theft Friday, BART Police reported.

BART cellphone thefts jumped this year, the agency has said. In 2015, there were 180 cell phone thefts on BART, increasing to 274 in 2016. In the first six months of this year, 225 cellphones were stolen, according to BART.

Around 3 p.m. Friday, a man reported to police that a suspect in his twenties dressed in all-black clothing unsuccessfully tried to steal the victim’s phone. The attempt occurred on a train at the Fruitvale station in Oakland, and the victim told police he was knocked to the floor, police said.

At 8:40 p.m., a victim reported that the cellphone had been snatched from the victim’s hand at the Union City station by a suspect in a white hooded sweatshirt who fled on foot, police said. Officers couldn’t find the suspect.

At about 9:30 p.m., a man told police two suspects stole his phone while he was on the stairs leading to the 16th Street BART station in San Francisco. Officers couldn’t find the suspects, described as wearing dark hooded sweatshirts.

Around 9 p.m., two people reported that their phones were snatched from their hands at the Coliseum station in Oakland by a group of young people who fled on foot, according to police.

Officers stopped a group in the parking lot and located one of the stolen phones. One victim identified a suspect as the person who stole the victim’s phone. The 14-year-old suspect was arrested on suspicion of theft, police said.

This is not the first time a group of young people committed thefts at the Coliseum station. In April, a mob of 40-60 young people streamed onto a BART train at the Coliseum, robbing multiple riders of bags and cellphones and injuring at least two people, according to BART officials.

Witnesses reported that the suspects jumped the fare gates at the Coliseum station around 9:30 p.m., then boarded a Dublin train and committed at least seven robberies, the agency’s police log said.

BART launched a public awareness campaign in July to battle cellphone theft. The campaign encourages riders to be more aware of their surroundings. It includes regular audio announcements on trains and in stations and an awareness poster for the trains.

The campaign encourages riders to protect their phones by keeping them secure, especially near train doors and while waiting on platforms.

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