Jackass death: police probe speed factor

Skid marks leading to the scene of where Ryan Dunne's car left the road and burst into flames in West Goshen, Philidelphia. Photo / AP

Jackass daredevil Ryan Dunn and his passenger died from the impact of a violent car crash and the resulting fire, according to a coroner's report.

The Chester County coroner on Tuesday listed blunt force trauma and thermal trauma as the official causes of death for both men.

Toxicology results will take four to six weeks to complete, coroner's office spokeswoman Patty Emmons said.

The 34-year-old Dunn and passenger Zachary Hartwell died early on Monday, shortly after leaving a pub in West Chester where Dunn had tweeted a photo of the pair and a third man drinking just hours before the crash.

The photo has since been taken down.

Barnaby's of America manager Jim O'Brien declined through an employee to speak to The Associated Press.

He told The Philadelphia Inquirer that Dunn was drinking with several friends at the bar but didn't appear drunk.

West Goshen Township police declined on Tuesday to discuss the ongoing investigation in detail but believe speed may have been a factor in the suburban Philadelphia crash.

A preliminary examination of the crash site suggested that Dunn's Porsche might have been travelling more than 100 mph (160km/h) in the 55 mph (88 km/h) zone when it jumped a guardrail, flew into a wooded ravine, struck a tree and burst into flames.

The 30-year-old Hartwell was credited as a production assistant for the second Jackass movie.

Dunn's brother, Eric Dunn, said in an emailed statement to the AP that his family was "devastated".

"We appreciate the support of Ryan's fans during this time, and we are grateful for your thoughts and prayers," he said.

"Ryan will be greatly missed, but he will forever remain in our hearts."

Mourners placed flowers and took photos at the accident scene in West Chester, while Facebook and Twitter were buzzing with condolences from fans around the world and friends from Hollywood to Chester County.

Among those expressing their sorrow online were Good Charlotte guitarist Benji Madden, reality TV star Brody Jenner and Dunn's Jackass movie and TV cohorts Bam Margera, Stephen "Steve-O" Glover and Jason "Wee Man" Acuna.

Glover tweeted: "I don't know what to say, except I love Ryan Dunn and I'm really going to miss him." Glover also cancelled six upcoming stand-up comedy shows in Sacramento, California, and the venue said it was issuing ticketholders refunds.

There was also criticism, most notably after movie critic Roger Ebert posted on Twitter that "friends don't let jackasses drink and drive".

Margera erupted in expletives on his own Twitter page. Ebert's Facebook page was flooded with derogatory posts and briefly taken down; Facebook apologised a few hours later and said the page was "removed in error".

Ebert responded on Tuesday that he didn't mean to be cruel and was "probably too quick to tweet" after the crash.

-AAP