Jackass daredevil Ryan Dunn and his passenger died from the impact of the violent car crash they were involved in and the resulting fire, according to a coroner's report.
The Chester County coroner 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.
Dunn was known for making viewers cringe and snicker through vulgar stunts with his cohorts in the multimillion-dollar Jackass TV and movie franchise.
Dunn, 34, and passenger Zachary Hartwell died early on Monday, shortly after leaving Barnaby's, a pub in West Chester, Pennsylvania. Dunn had tweeted a photo of the pair and a third man drinking just hours before the crash, but the photo has since been taken down.
The manager of Barnaby's, Jim O'Brien, told the Philadelphia Inquirer that Dunn was drinking with several friends at the bar but didn't appear drunk.
A preliminary examination of the crash site suggested Dunn's Porsche may have been travelling more than 100mph (160kph) in the 55mph zone when it jumped a guard rail, 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, while Facebook and Twitter were full of 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 co-stars Bam Margera, Stephen 'Steve-O' Glover and Jason 'Wee Man' Acuna.
There was also criticism for movie critic Roger Ebert, who, on hearing of the circumstances of Dunn's death, had tweeted that "friends don't let jackasses drink and drive". His Facebook page was flooded with derogatory posts and briefly taken down, though Ebert has since said that he didn't mean to be cruel and was "probably too quick to tweet" after the crash.