Police in Prince William County said they are looking for this man, who allegedly assaulted a bus driver in Woodbridge, Va. (Courtesy of Prince William County Police)

Authorities are looking for a man who allegedly ran alongside a bus, kicked and broke a window, then got on the bus and assaulted the driver in Woodbridge, Va.

The incident unfolded around 8:15 p.m. Tuesday near Minnieville Road and Prince William Parkway.

The bus driver works for the Potomac and Rappahannock Transportation Commission. He told Prince William County Police that as he was driving the bus, he saw a man running alongside the vehicle.

When he stopped at a traffic light, the man started “banging on the bus and demanded that the door be opened,” according to a police statement. When the driver refused to open the door, the man stood in front of the bus so the driver couldn’t move the vehicle.

The man then started to kick the bus door and kicked out one of the lower windows on the bus, police said. He then reached inside and opened the door.

The man, police said, then got on the bus and sprayed the driver “with an unknown substance.” The driver sustained minor injuries, and the attacker fled.

A K9 unit looked for the suspect but could not find him. Police said the incident remains under investigation.

Police released a video surveillance photo of the suspect. They described him as “dark-skinned” and standing 6 feet tall. He has short, black hair and brown eyes. He was last seen wearing a white shirt and pants.

Anyone with information is asked to call 703-792-7000.