PITTSBURG (CBS SF) – Bay Area law enforcement agencies launched an intense manhunt Wednesday for a gunman in a white Mercedes who was wanted in connection with the fatal shooting of a mother of four on Highway 4.

The family of Shanique Marie told KPIX 5 that she was killed in the shooting. Pittsburg police later confirmed the identity of the shooting victim.

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The 25-year-old leaves behind four children who are now orphaned. Their father was killed in a double homicide last May in Pittsburg.

Family initially reported Marie was pregnant with a fifth child, but that was later determined to be incorrect. They were devastated after learning their daughter was killed.

“This is a young lady gunned down like she was nothing,” said Patrick Johnson, the victim’s uncle.

Her uncle asked any witnesses with information to talk to authorities and demanding justice.

“Somebody seen something. We are begging you. I am begging you. Please come forward,” said Johnson. “She has four kids. Four kids!”

California Highway Patrol officials said the shooting was first reported at 10:48 a.m. on westbound Highway 4 just east of Railroad Avenue.

Marie and a man were in a black sedan and injured when a gunman opened fire on their vehicle. Police said the shooting was not random and that the couple had been targeted.

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Both occupants were suffering from injuries as a result of gunshot wounds and the subsequent collision, as their vehicle lost control, striking the dirt embankment and rolling over after the shooting.

They were taken to John Muir Hospital for treatment where the woman succumbed to her injuries and the man was in critical condition.

Footage shot by Chopper 5 showed the black Lexus sedan that had crashed with debris littered around it and a number of CHP vehicles. There was also a white van stopped in the middle of the highway’s westbound lanes.

The family said Marie became distant recently when she started dating her boyfriend, the owner of the Lexus that was shot up.

At about 2:10 p.m., authorities said the three left lanes of Highway 4 were re-opened. The right lane remained closed. Motorists are advised to expect delays and to slow or move over for workers. The fourth lane re-opened at about 3:40 p.m.

The Pittsburg Police Department was taking the lead in the fatal shooting investigation, authorities said.

“I can tell you that as law enforcement, we are very concerned,” said Pittsburgh Police Captain Ron Raman.

There have been at least three other shootings on Highway 4 since November and 18 or more across various highways in Alameda and Contra Costa counties in a recent flurry of highway violence.

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