MILLBRAE (CBS SF) — BART police, in cooperation with the Clayton and Concord police departments, arrested a suspect wanted in connection with a Friday morning sexual assault at the Millbrae BART station.

The arrest took place Friday night at a residence in Concord, BART said in a statement.

The alleged assault happened sometimeĀ in the overnight hours when BART trains were not in service.

A station agent spotted a woman in the station via a closed-circuit television before BART service opened and called police. Once officers reached her, she stated that she had been assaulted, police said.

The suspect was identified as 38-year-old Roberto Marrenco, who police described as a transient.

The suspect vehicle was identified as a white Ford cargo van with California license plate number of 7V40543.

Detectives were trying to determine whether Marrenco and the victim know each other. A working surveillance camera was in the elevator where the alleged assault happened and police were reviewing the footage.

Anyone with information on the suspect was urged to call BART police at 510-464-7045.