A motorcyclist has been critically injured after his bike crashed into a tree before bursting into flames.

The crash happened at the intersection of Goondah and Coolalie St, Villawood in Sydney’s west just after 10pm on Thursday.

The 29-year-old man was set alight, with residents nearby helping to put out the flames.

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They performed first aid on the man until help arrived.

He was treated by paramedics at the scene and then taken to Royal North Shore Hospital in a critical condition, and is currently into an induced coma.

The bike sustained “extensive damage” in the blaze, police said.

Initial investigations indicate the man was not wearing a helmet when his bike crashed.

“Officers from Bankstown Police Area Command established a crime scene that was examined by specialist police,” NSW Police said.

“An investigation into the circumstances surrounding the crash has commenced.”

Anyone with information has been urged to contact Bankstown Police Station or Crime Stoppers.