A thief on a bicycle was injured and arrested after he rode alongside a car on a San Francisco street, reached through an open window and snatched a passenger’s cell phone before crashing, police said.

The brazen theft occurred just after 11 p.m. on Tuesday in the 1400 block of Valencia Street in the Mission District, police said.

The 30-year-old victim was sitting in the front passenger seat of the moving vehicle talking on his cell phone when the bicyclist’s reached in and grabbed the device, said Officer Carlos Manfredi, a spokesman for the San Francisco Police Department. A brief struggle ensued over the phone and the bicyclist, whose name was not released, lost his balance, crashed into the side of the car and fell to the pavement, he said.

“The bike got caught under the tire of the vehicle,” Manfredi said.

When police officers arrived, they initially thought they were responding to a collision between a bicyclist and a vehicle. Then the victim, whose name was also not released, pointed out that the injured bicyclist was still in possession of his stolen cell phone, Manfredi said.

After being treated by paramedics for minor injuries, the suspect was arrested on suspicion of robbery.

Bill Hutchinson is a San Francisco Chronicle staff writer. Email: bhutchinson@sfchronicle.com Twitter: @bill_hutchinson