Two men have been seriously injured when their motorised bicycles collided and burst into flames on the NSW north coast.
Shortly before midnight (AEST) the two men, aged 25 and 41, were travelling west along Ryan Street, South Grafton, when their petrol-driven bicycles collided, police said.
Flames engulfed both riders and a passer-by used a garden hose to douse the flames.
The 41-year-old man sustained extensive third degree burns and head injuries and was critically ill in hospital on Thursday morning.
The younger man suffered serious burns to his left leg and cuts to his head, and is in a serious condition.
Both men were taken to Grafton Base Hospital before being airlifted to the burns unit at Sydney's Royal North Shore Hospital.
Both bicycles have been seized for forensic examination.