Police and firefighters responded to a report of a car fire in the 2300 block of Grant Avenue at about 7:30 p.m.
Arriving officers found a four-door Ford sedan on fire in a driveway, police said. The fire started in the car's passenger area and was quickly extinguished, Lt. Mark Gagan said.
Two people, possibly juveniles, were seen running from the area just before the fire, Gagan said. Neither matches the description of the suspect in a rash of more than 20 vehicle fires throughout Contra Costa County in recent months.
However, Tuesday's fire was definitely a criminal act, Gagan said.
"We don't know the motivation, if it's a copycat," he said.
Richmond police and firefighters also responded to a minor structure fire at a house in the 1300 block of Coalinga at 10:13 p.m.