The first vehicle, a minivan, was struck by one or more bullets at about 4:15 a.m. while heading east on Highway 16 between the Tacoma Narrows Bridge and Jackson Avenue, the State Patrol reported. The driver was not struck or injured.
The second vehicle, a full-sized sedan, was hit by several rounds while driving north on Interstate 5 between 56th Street and 38th Street. That driver was not hurt, either.
"We need to find any possible witnesses that may have seen anything out of the ordinary this morning on SR-16 and I-5 around the time of these incidents," the State Patrol said in a prepared statement.
Specifically, state troopers say, that includes pedestrians, vehicles parked on the shoulder, odd noises or anything else that someone may have seen.
The State Patrol says it's not clear whether the incidents are related or were two separate acts. The shootings remain under active investigation.
Anyone with information is asked to contact State Patrol Detective Vic Mauro at (253) 538-3176.