(CARSON, Calif.) — Authorities are on the hunt for a gunman responsible for five shootings in a two-week period in Carson, Calif., and the neighboring Harbor Gateway area of Southern California.

The gunman, armed with a shotgun, hit a pedestrian as well as four motorists or their vehicles on or around the heavily traveled 110 Freeway, according to the Los Angeles County Sheriff’s Department. One motorist was seriously injured.

The first shooting was reported April 18, when a woman was shot in the arm as she walked down Main Street, authorities said. Four days later, a woman’s car was hit by birdshot as she drove down Normandie Avenue.

The following day, according to officials, the gunman fired on another vehicle at the Carson Street freeway exit.

On April 26, there were two more shootings an hour apart, authorities said. First, a car headed down Figueroa Street was hit, and less than an hour later another motorist was shot in the ear as he drove his 2008 Honda Accord on the 110 Freeway.

“All shootings happened in the same general area,” said Sgt. Marc Lucia of the L.A. County Sheriff’s Department. “The shots failed to penetrate the car except in the case where it hit a windshield. The rounds he used were not high-powered, [but were] more of a low-capacity round like birdshot.”

Both injured shooting victims were treated at a hospital and released.

The Los Angeles County Sheriff’s Department and the California Highway Patrol investigators are meeting to compare notes, tips and a description of the suspect Wednesday.

“We don’t have a description of the suspect yet, but both teams are working together to provide more details,” said Sgt. Dave Nelms of the California Highway Patrol.

Nelms urged residents to be vigilant and aware of their surroundings.

“Often, people are in a comfort zone when they enter their vehicles and drive but it’s important to be alert,” he said. “If you see anything that is out of the ordinary, call the police.”

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