By The Associated Press A man suspected of shooting and killing his pregnant girlfriend while she was driving him and her two children turned himself in Monday. Stephen Mark Picart, 33, surrendered at a South Los Angeles police station a day after Sharon Carter was shot in the back of the head as she was driving her sport utility vehicle in Watts, police said. Picart of Los Angeles was booked on suspicion of murder and held without bail, said officer Mike Lopez, a police spokesman. Police said they didn’t know if Picart had retained an attorney yet. His number was unlisted. After Carter was shot, her SUV hit two cars and came to a stop, police said. The gunman then fled. Her sons, ages 4 and 14, were not injured. They were placed in protective custody. Investigators suspect Picart, whom they described as Carter’s “significant other,” was in the vehicle and arguing with the 31-year-old woman. Police and family members said Carter was pregnant with Picart’s child. Authorities believe he surrendered because of “pressure from the family, pressure from a very religious upbringing and then pressure from (police) and the rest of the community,” Deputy Chief Charlie Beck said. Carter’s sister, Christi Antwine, told KABC Channel 7 the boys were distraught after witnessing the shooting. “The hardest thing is to tell a 4-year-old child that they’ll never see their mother again,” Antwine said.160Want local news?Sign up for the Localist and stay informed Something went wrong. Please try again.subscribeCongratulations! You’re all set!