A 79-year-old South Riding woman was killed Christmas morning when the car she was riding in was struck by an allegedly intoxicated driver, the Loudoun County Sheriff’s Office said.

Rashida Begum and four others were stopped at a red light near South Riding Boulevard at 8:20 a.m. Wednesday when a pickup truck slammed into them from behind, authorities said.

Begum, a passenger in the sedan, died at the scene. Four other occupants of the vehicle were hospitalized, including two with life-threatening injuries. It was not clear where the victims were headed when the crash occurred.

Authorities identified the truck driver as Martin V. Chavez, 56, of Sterling. He was charged with involuntary manslaughter and driving while intoxicated and is being held without bond.

A passenger in the truck suffered serious injuries.

The Loudoun County Sheriff’s Office Crash Reconstruction Unit is investigating.