Police are searching for a driver who fired into another vehicle before fleeing police on the Capital Beltway’s Outer Loop in Silver Spring, Maryland, Monday afternoon.

A Montgomery County police officer pulled over a blue Hyundai sedan near Md. Route 650 around 3 p.m. after having observed it driving erratically, police said in a news release.

While conducting the traffic stop, an unidentified witness drove up to the officer and informed him that the Hyundai’s driver had just been involved in a shooting.

The Hyundai’s driver sped off before the officer could investigate further. State and county police canvassed the area of I-495 near Silver Spring but were unable to find the driver and vehicle involved.

Maryland State Police determined the driver had fired a single bullet into the passenger door of another vehicle along the Outer Loop. Troopers later made contact with the victim, who was not injured. The person’s vehicle was searched for additional evidence.

Investigators were still working Tuesday morning to identify the shooter and pin down a motive. Police described the suspect as a “heavy set African-American man with facial hair, wearing a red shirt.”

They asked anyone with information or who witnessed the incident to contact state police at 301-424-2101. Tips can be submitted by email to michael.obrien@maryland.gov.