Paul Walker's Death: Latest Developments in the Investigation

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Paul Walker

Law enforcement officials say speed was a factor in the car crash that killed Walker and Roger Rodas, CEO of the actor's company Always Evolving.

As Hollywood mourns Paul Walker, who died Saturday in a fiery car crash, law enforcement officials are still trying to figure out what led to the accident.

Walker, 40, died during a break from shooting Fast & Furious 7. He had returned to Southern California and died when the limited-edition Porsche in which he was a passenger crashed in Valencia.

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The driver was Roger Rodas, a well-respected financial adviser and the CEO of Walker's company Always Evolving. (The duo met because of their shared passion for cars.) Rodas also died in the crash.

A slew of reports and statements made by the Los Angeles County Sheriff's Department offer new details about the investigation, which is still ongoing.

According to law enforcement officials, the Porsche was found smashed into a light pole and tree and engulfed in flames when they arrived on the scene. Witnesses tried to put the fire out with fire extinguishers, according to reports, but both Walker and Rodas were pronounced dead at the scene.

Police told ABC News that the force of the impact caused a chunk of the car to fly several feet into a nearby building, breaking a window. One witness told the Los Angeles Daily News that the flames were up to 20 feet high.

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"Speed was a factor in the solo vehicle collision," LASD said in a statement over the weekend. Deputy Mark Pope told the Chicago Tribune that officials had not yet been able to determine how fast the car was going.

The Los Angeles Times reported that "looping tire tracks were visible on the asphalt nearby" the crash. Investigators have not determined whether the tracks are related to the car crash.

Meanwhile, TMZ has spoken to sources at Always Evolving -- which Walker and Rodas co-owned -- who have suspicions about the cause of the crash. They believe it was the result of mechanical failure, possibly a steering fluid leak. They say they saw evidence of a fluid burst at the scene and point out that if Rodas had lost control, the skid marks would have shown swerving.

Law enforcement has said that no new update is likely Monday.

The L.A. County Coroner's office said Monday morning that the autopsies are on hold: "The examinations are on hold today. Most likely pending identification efforts."

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Walker's and Rodas' bodies were burned so badly that their dental records reportedly are being used to identify them.

Walker had been in Valencia, just north of Los Angeles, for a car show and toy drive set up through his charity, Reach Out WorldWide. In 2010, he flew to Chile to help those injured in the 8.8 magnitude earthquake and earlier was involved in the effort to assist survivors of the earthquake in Haiti.

Following the crash, a fan-made memorial popped up at the site. Tyrese Gibson, Walker's friend and co-star in the Fast & Furious movies, broke down in tears Sunday while visiting the site.