RIP

This is the dramatic moment when a cop had to physically wrestle one of Paul Walker's friends away from the crash scene ... seconds after it became clear Paul could not be saved.

TMZ broke the story ... Paul's friends rushed to the scene -- one even grabbed a fire extinguisher and desperately tried to extinguish the flames.

When the fire dept. arrived they tried to pull Paul's friends away. One of Paul's longtime friends, a guy named Nute, was so overwrought with emotion, he punched a firefighter. We're told Sheriff's deputies put Nute -- and several other of Paul's friends -- in custody, but let them go when they realized the circumstances.

Cops now believe Paul and the driver of the Porsche may have been in a street race with another car at the time of the crash and are looking for footage and witnesses.

Cops are investigating the possibility that Paul Walker was in the middle of a high-speed street race with another car at the time he crashed and died this weekend ... TMZ has learned.

Law enforcement sources tell us ... investigators have received tips that Walker and the man driving the Porsche, Roger Rodas, had been racing prior to the crash ... and the high speed may have contributed to the wreck that killed both men.

Sources say ... the area where the crash occurred has a history of being a popular street racing location.

We're told cops are on the hunt for video and witnesses that could prove another car was involved.

The exotic sports car in which Paul Walker violently died, crashed as a result of mechanical failure -- very possibly a steering fluid leak ... this according to sources closely tied to the auto shop where the vehicle was stored and maintained.

Sources connected to Always Evolving -- the shop co-owned by Walker and the Porsche driver Roger Rodas -- tell TMZ they saw evidence of a fluid burst and subsequent fluid trail before the skid marks at the accident scene.

The AE sources point to the fact there is a noticeable absence of skid marks until just before the point of impact. They say if Roger had lost control the skid marks would show swerving, but instead the marks were in a straight line. They feel this cements the theory the driver didn't have steering control.

Also suspicious -- the fire spreading so quickly in the front of the car. The sources say flames would be expected in the rear where the engine is ... but fire in the front reinforces their theory of a fluid leak of some sort.

We're told the $500,000 Carrera GT was NOT modified and was driven rarely so they believe any failure must be a factory defect.

Paul Walker fans have been heading to Valencia, CA in droves ... building out a massive vigil for the actor on the spot where he died.

Fans began to gather literally hours after the fatal crash on Saturday evening ... and by Sunday night, the memorial had grown exponentially ... with hundreds of flowers, candles, photos trinkets and letters.

As we previously reported, Walker's "Fast and the Furious" co-star Tyrese Gibson visited the crash scene yesterday ... and broke down crying when he arrived.

Matt Damon finally said what everyone in Hollywood has been thinking -- Paul Walker's death is "f**king horrible."

Damon was arriving at LAX with his wife yesterday when he was asked about the tragedy involving the "Fast and the Furious" actor ... and was as brutally honest as he could be.

Damon said the two knew each other -- though it's unclear how well. It doesn't appear the two ever worked together.

Still, Damon's words couldn't ring more true -- Walker was known around town as one of the nicest guys in the biz ... and was attending a charity event at the time of the fatal crash.

Paul Walker may not have ever gotten into the car that took him to his death if it hadn't been acting up moments before the crash ... TMZ has learned.

Paul showed up Saturday for a fundraiser at Always Evolving -- Roger Rodas' high end auto shop that specializes in exotic cars. Paul had a stake in the shop.

Sources connected to Roger tell TMZ when Paul arrived ... Roger was watching one of his employees try in vain to back the Carrera GT into the shop, but it kept stalling. Roger decided to take matters into his own hands ... told the worker to get out and took the wheel himself.

As Roger began to back into the garage ... Paul came up and said he hadn't driven in the Porsche yet -- so he jumped in the passenger seat and they took a 20 minute drive.

The fatal accident happened on the way back from that drive -- just 500 yards from the shop.

Paul's best friend from childhood, Nute, grabbed a fire extinguisher and was among the first to arrive on scene. We're told Nute frantically tried to extinguish the flames ... even though it appeared to him both men were already dead.

Tyrese Gibson was overcome with grief Sunday afternoon when he showed up to the crash site where his "Fast and Furious" co-star Paul Walker died less than 24 hours before.

Tyrese paid tribute to Walker during a quick stop at the Santa Clarita crash spot moments ago ... the same place fans are leaving tons of flowers and various tokens in honor of Walker.

Gibson is clearly falling apart while visiting the death site ... and everyone around him is completely silent while he mourns.

3:00 PM PST -- Tyrese took a piece of the crash wreckage home with him and posted a pic of it online afterward.

Paul Walker's daughter does NOT have a public social media page ... and his reps have already shut down one site run by an impostor.

Multiple news outlets posted stories Sunday morning saying Paul's 15-year-old Meadow Walker -- pictured above with her dad back in June -- paid tribute the actor on her Facebook page after the crash ... only problem, it's run by a fake.

The new "Fast and Furious" movie was scheduled to shoot key scenes with Paul Walker this week -- and on the heels of his death, several members of the cast and crew say they won't be returning to the set anytime soon ... TMZ has learned.

Sources close to the production tell us most of the actors and crew were supposed to fly to Atlanta this weekend to resume filming on Tuesday ... but they're all expecting a halt in production.

Universal -- the studio behind the movie -- hasn't announced when, or if, they'll start shooting again ... but we're told some of the main stars are too distraught to work anyway.

According to our sources ... most of this week's scenes centered around Paul, so even if Universal were to go forward ... it would need major rewrites.

Ultimately, the biggest hurdle to completing 'FF7' could be the emotions of the actors. As one source put it, "No one wants to even think about the movie. Period."

Paul Walker's body was burned so badly the coroner needs his dental records to identify the body ... TMZ has learned.

A rep for the L.A. County Coroner tells us ... the bodies of Paul and his friend/business partner Roger Rodas are currently unidentifiable and their autopsies will be delayed until later this week.

We're told the coroner is waiting on both sets of dental records before proceeding.

Rodas -- who was driving the Porsche yesterday -- was friends with Walker for nearly a decade ... and Roger has been credited with helping Paul start his race shop.

The two also joined forces to create the "Reach Out World Wide" Foundation to help disaster relief in other countries -- and as we first reported ... the group was behind yesterday's fundraiser for typhoon relief in Santa Clarita.

Paul's rep says Roger and Paul were leaving the event when they wrecked.

Rodas was 38 years old.

Moments before Paul Walker took what turned out to be a fatal ride -- he posed proudly next to the exotic car that exploded on impact in the deadly accident.

Paul was photographed with the red 2005 Porsche Carrera GT that belonged to his friend Roger Rodas. They were attending a fundraiser in Santa Clarita, CA.

We're told the photos and video were taken about 30 minutes before the accident.

As TMZ first reported ... Paul had put together the charitable event -- through his Reach Out Worldwide organization -- to support typhoon relief efforts in the Philippines.

Paul was the passenger in the Porsche when Rodas lost control and slammed into a tree. The car exploded, and the Sheriff's Department says speed was a factor.

Paul Walker fans paid tribute to the 40-year old actor last night by holding a candlelight vigil on the site where he died.

The fans showed up in Santa Clarita Saturday evening ... leaving flowers and lighting candles in Paul's memory.

The vigil was held very shortly after law enforcement cleared the scene -- removing the bodies of Paul and the driver Roger Rodas ... as well as the charred wreckage of Roger's Porsche Carrera GT.

Paul Walker -- best known for his role in "The Fast and the Furious" movies -- died Saturday afternoon after a single-car accident and explosion in Southern California ... TMZ has learned.

The accident happened in Santa Clarita -- north of Los Angeles -- and Paul was the passenger in the two-seater Porsche Carrera GT when the driver somehow lost control and slammed into a post or a tree ... and the car burst into flames.

Several of our sources -- some of whom were at the scene of the accident -- tell us a friend of Paul's was driving and was also killed in the fiery wreck.

Cops say speed clearly played a major factor in the accident, but an exact cause has not been determined yet.

Paul was 40 years old. He leaves behind a 15-year-old daughter named Meadow.

Paul's rep tells us he was in Santa Clarita for a car show -- organized by Paul and his charitable organization Reach Out Worldwide -- to support the Philippines typhoon relief effort.

Several of his friends were attending the event ... which was very near to where the deadly accident happened.

One of Paul's friends talked to a TMZ photographer ... describing the scene ... and his efforts to save Paul from the burning car.

Paul took a pic with a fan at the event earlier on Saturday, and the guy posted it ... noting how happy Walker was just hours before the crash.

The fan added, "The world lost an angel in Paul. He dedicated so much of his life to helping disadvantaged kids and people who are in need. I'm gonna do whatever I can to keep Paul's goals for the charity alive."

Conrad Murray is pointing the finger back at Michael Jackson's Estate -- after it threatened to sue over stories he told about holding MJ's penis -- claiming the Estate was the first to open the can of worms that is MJ's medical secrets.

As we reported, the MJ Estate is threatening to sue Murray for blabbing to the media about the singer's sordid medical details -- including a story about holding Michael's penis every night. The Estate is claiming Murray has been violating the doctor-patient privilege by running his mouth in public.

But sources close to Murray tell us, he's not scared ... because he believes once Katherine sued for wrongful death (and exposed a bunch of MJ's medical secrets at the trial) she compromised the doctor-patient privilege on her son's behalf.

The woman whose son was killed while photographing Justin Bieber's Ferrari January 1 claims not one but TWO cars struck the photog. The second driver is wanted for felony hit-and-run and TMZ has learned the hit-and-run vehicle fits the basic description of an SUV in Bieber's entourage.

Bieber was NOT in the Ferrari. Lil Twist was behind the wheel when he was allegedly speeding on the 405, and a CHP officer pulled him off the Freeway. The deputy spoke to Twist and let him go, and then told photog Chris Guerra -- who was standing on the side of the road -- to get out of the area. As Guerra walked across the road, he was struck by a car, and shortly thereafter hit by a second vehicle.

Law enforcement sources tell TMZ -- based on surveillance video and forensic evidence -- the second vehicle that struck Guerra was a black, high-profile SUV that was either a Range Rover or a Hummer.

Guerra's mom believes it's possible the SUV could have been someone from Bieber's camp either trailing the Fererari or coming to assist Twist. Cops are not embracing or discounting the mom's theory ... and the investigation is ongoing.

Guerra's mom wants the LAPD to show her the surveillance footage so she can see for herself, but they've told her it's an ongoing investigation so no dice.

We've contacted Bieber's camp for comment, but haven't heard back yet.

Brian Griffin is dead and he's not coming back ... at least that's the way it appears ... because TMZ has learned, the dog that's replacing him on "Family Guy" has already been booked for several upcoming episodes.

As we reported, former "Sopranos" star Tony Sirico will be voicing Vinnie -- pictured above -- after Brian was killed off in Sunday night's episode.

There's been a lot of hopeful speculation that Brian's death was a one-episode gimmick -- and that the dog will inevitably come back -- but that doesn't seem likely. A rep for Sirico tells us, Vinnie the Dog has already been voiced for another 6 or so episodes.

We're told there's probably even more to come after that, too. Translation: Brian's not coming back ... at least for a very long time ... and probably never.

Sirico doesn't exactly have a clear conscience about all of it though -- his rep says the actor feels horrible that Brian was killed off because the death of any character is sad ... especially a fan favorite ... but c'est la vie.

As for why Brian got the chop, a producer for the show said they just wanted to shake things up.