Police investigators who are working on Fast and the Furious star Paul Walker's death have ruled out drag racing as the cause of the tragic crash, reported by CNN. Walker died on Saturday after the Porsche GT Carrera being driven by friend Roger Rodas went ablaze in Santa Clarita, California.

Flowers and movies left by fans are seen at the scene of the car crash where actor Paul Walker was killed in the Santa Clarita area of Los Angeles. (Reuters)

Drag racing was believed to have played a role in Walker and Rodas's death after the investigators received a phone call stating that another car was at the scene when the Porsche GT hit a light pole before catching fire. However, a spokesperson of the Los Angeles County Sheriff said on Monday that there was no proof that another car was on the scene when the accident occurred.

Several spectators have also confirmed that they only saw the red Porsche on the road when it crashed.

"That lead (drag racing) has been exhausted and determined that was not to be credible," said Sgt Rich Pena.

Thus, the investigation is now focused on the speed of the Porsche. "Speed was a factor in the crash," said the Los Angeles County Sheriff spokesperson. It was reported that a speed limit sign which reads 45mph was affixed on the light pole that Walker's car slammed into.

By Sunday, the wreckage of the car crash was already cleared and removed. Fans pay their respects by putting flowers and candles at the crash site. Walker's Fast and the Furious co-star Tyrese Gibson also visited the area of the accident where he got emotional and broke down in tears.

Watch Tyrese as he visit Walker's crash site below.

 Video courtesy: YouTube/Treze

Meanwhile, fans, friends and Hollywood celebrities continue to mourn for Walker's death. His funeral arrangement is underway and it has been reported that Gibson is helping the family organise the memorial service.

Walker was only 40 at the time of his death. He was survived by his 15-year-old daughter, Meadow.

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