Three people were injured, including a 2-year-old child, when an unknown assailant opened fire on an East Bay freeway Monday night, authorities said, the latest in a string of shootings on highways in the area.

Around 7 p.m., officers from the California Highway Patrol responded to reports of the shooting on eastbound Interstate 80 near Richmond Parkway in Richmond, CHP officials said.

The first officers on the scene found a car that had been hit by gunfire at a nearby gas station where the occupants had pulled off the freeway to seek help.

The vehicle had been struck by at least one bullet, which shattered a side window. A 2-year-old child riding inside the car suffered minor injuries from being hit by flying glass, the CHP said.

Soon after, a female teenager and a man in his 20s were dropped off at a nearby hospital, both suffering from non-life threatening gunshot wounds, the CHP said. Officials believe they were injured in the same incident and were apparently the intended targets.

The other car that was hit, the one carrying the child, appeared to have been caught in the crossfire, the CHP said.

It was the fifth shooting on Interstate 80 since November.

On Nov. 2, a man was wounded when he was shot while driving on the freeway near San Pablo Dam Road. About a week later, a man was killed and a woman was injured in a car-to-car shooting on the same roadway just a few miles east of Monday night’s incident near Pinole Valley Road. Later that same month, a person was injured by flying glass when their car was hit by gunfire while traveling on I-80 in Berkeley.

On Dec. 17, a man was wounded in another apparent car-to-car shooting on the freeway near San Pablo Dam Road in San Pablo, the CHP said. The investigation into that shooting, which occurred around 3 p.m., briefly closed the freeway during rush hour.

It was unclear whether any or all of the incidents were related, but officials said the investigation is ongoing and encouraged anyone with information to contact the CHP at (707) 551-4100.

Kale Williams is a San Francisco Chronicle staff writer. E-mail: kwilliams@sfchronicle.com Twitter: @sfkale