A man was booked into jail this Monday morning, May 21, on suspicion of fatally shooting an MTA bus driver in West Hollywood.

Anthony Craig Chambers, 41, of Los Angeles was arrested at the scene of Sunday morning’s shooting and booked on suspicion of murder at the West Hollywood Sheriff’s Station, where he was being held in lieu of $1 million bail, according to the Los Angeles County Sheriff’s Department.

Chambers was detained after he was seen climbing out of the window of the Metro bus on Santa Monica Boulevard west of La Cienega Boulevard following the fatal shooting at 9:09 a.m. Sunday, said Deputy Lillian Peck of the Sheriff’s Headquarters Bureau. Two guns were found on the bus, according to broadcast reports.

The driver, Alan Thomas, 51, was rushed by Los Angeles County Fire Department paramedics to nearby Cedars-Sinai Medical Center, where he died at 9:30 a.m. Sunday. The motive for the shooting was not immediately known.

Metro spokesman Rick Jager said the driver had been piloting a Route 105 bus east on Santa Monica Boulevard when he was shot by a passenger. Route 105 runs from West Hollywood south on La Cienega Boulevard, and then east on Vernon Avenue. An MTA bus yard is located near that intersection, which is one block from the West Hollywood sheriff’s station.

“From our perspective we are very concerned about this incident,” Jager said. “It is a very highly unusual situation. Our CEO went to the scene to express his condolences,” the MTA spokesman said. “We are very concerned about our fellow employees.”