Authorities say a car driven by the U.S. ambassador to Malta crashed into a drainage ditch in Southern California, killing a nun and injuring a 94-year-old pastor.

The nun and pastor were passengers in the car driver by Ambassador Douglas Kmiec (kah-MEK'), 58, the California Highway Patrol said. Kmiec also suffered moderate injuries in Wednesday's one-vehicle crash.

CHP Officer Leland Tang said Kmiec was driving a Hyundai Accent on Mulholland Highway near Calabasas when the car veered into a drainage ditch and crashed.

Sister Mary Campbell, 74, of Our Lady of Malibu Catholic Church died at the scene, while Pastor Emeritus Monsignor John Sheridan received moderate injuries, Tang said.

The three had attended an anniversary celebration at a Woodland Hills high school and were returning to the church when the crash occurred, The Malibu Times reported.

Our Lady of Malibu Parish Manager Peggy Thomas told the newspaper that Sheridan underwent surgery and was in critical but stable condition. Kmiec also underwent surgery and was in stable condition, the Times reported.

Kmiec was sworn in as U.S. ambassador to the island nation of Malta in September 2009. He is a professor of law at Pepperdine University.