The 34-year-old daredevil and an unnamed second person passed away in a car crash in Pennsylvania early on Monday, April Margera - the mother of his 'Jackass' co-star and close friend Bam Margera - has confirmed to gossip website TMZ.
According to reports, Ryan's Porsche flew over a guardrail on Route 322 at around 3am, hitting a tree before bursting into flames.
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It is not known who was driving the car.
Just a few hours before the accident, Ryan – who appeared in all of the 'Jackass' movies – posted a picture on his twitter page of himself drinking with friends.
In addition to being part of the 'Jackass' crew, Ryan – who turned 34 just over a week ago - appeared alongside Bam in 'Viva La Bam' and in his friend's 2003 movie 'Haggard', as well as MTV show 'Homewrecker'.