Paul Walker, the screen actor best known for his role in the “Fast & Furious” franchise as Brian O’Conner, died Saturday in a car wreck in Santa Clarita, Calif. He was 40. At a makeshift vigil Monday night at the site of the crash, Walker’s fellow actor Vin Diesel called him “an angel in heaven,” the Associated Press reported.

Walker was in the passenger seat of a Porsche that his friend Roger Rodas was driving, and both lost their lives when the car left the road, collided with a lamp post and a tree, and burst into flames.

Walker and Rodas had just left an event for Walker’s charity, where Walker’s girlfriend and daughter learned of his death, according to Hollywood Life. Walker and his girlfriend, Jasmine Pilchard-Gosnell, 23, had been together for about seven years.

Authorities said that while the area in which Walker died is a popular with street racers, Rodas and Walker were not racing another vehicle at the time. Investigators believe that speed was a factor in the crash, but have not said why the Porsche left the road.

The car, a 2005 Carerra GT with 3,283 miles, was notoriously difficult to handle, according to Autoweek. Citing unidentified sources, TMZ speculated that leaking steering fluid could have caused the crash and the explosion. A lack of skid marks on the road suggested the wheels of the car were not responding to the steering wheel, and while the engine is in the back of the car, the flames engulfed the front as well, suggesting a leak. Even a small bump in the road could have damaged the car, the gossip site reported.

Walker’s latest film, “Hours,” will be released this month. He plays a father who must keep his newborn daughter alive in a New Orleans hospital that has lost power during Hurricane Katrina. He told the Associated Press three weeks ago that his relationship with his 15-year-old daughter, Meadow, had inspired his work in the film.

“I’m five times the father that I was five years ago. Your head’s more in it. Your heart’s more in it. You can’t force it,” he said. Meadow had recently left her mother in Hawaii to live and travel with her father.

“Brick Mansions,” another film featuring Walker, is scheduled for release next year. The next installment of the “Fast & Furious” franchise, “Fast & Furious 7,” is to be released in July, but Walker and the rest of the crew had not finished shooting it when he died.

Universal Pictures has not yet revealed its plans for the film. As CNN reported, the studio might reproduce Walker’s face digitally or use another actor to replace him.

See images of other celebrities who have died this year in the gallery below.