A 19-year-old California man has been arrested and charged with multiple counts in a hit-and run that killed a pregnant teenager and left her baby in critical condition.

Authorities said Thursday that hospital staff delivered the teenager’s baby after the crash, but the mother did not survive, KABC reported.

Isaac Blackhorse Garcia has been charged with murder, hit and run resulting in death, and unlawful sex with minor.

Blackhorse Garcia was reportedly in a sexual relationship with the victim’s underage sister. He was dropping the sister off at her home in Riverside when family members approached his car. He sped off, striking the victim with his car.

He was later arrested in Moreno Valley.

The victim’s name has not been released.

Detectives say they believe Blackhorse Garcia may have sexually abused other minors and ask anyone with information to contact them at (951) 353-7135 or (951) 353-7104.