SONORA (CBS13) – A Tuolumne County doctor has been arrested in a deadly hit-and-run crash in Fresno County.

The CHP says Dr. James Comazzi was arrested following an 8-month investigation. He’s accused of hitting and killing a 26-year-old woman along Highway 99 back in February.

The woman was pulled over, helping another driver when she was killed.

Investigators say an anonymous tip led them to Comazzi. He’s facing manslaughter and hit-and-run charges. Comazzi is a cardiologist at Adventist Health in Sonora.