Police were trying to discover today how a man came to be found naked and severely burnt in a road.
The 24-year-old Polish man was found on Barrowby Road in Grantham, Lincs, at about 10.20pm on Saturday.
He was treated at Grantham Hospital and Nottingham's Queen's Medical Centre before being transferred to a specialist burns unit in Selly Oak hospital, Birmingham.
Lincolnshire Police said today that he remains in the hospital's intensive care unit, where his condition is believed to be life-threatening with 70-80 per cent burns to his body.
A spokesman said an investigation has been launched to find out what happened to the man, who is believed to live in Norton Street, Grantham.
Detective Inspector Helen Evans, of Grantham CID, said: "We need to speak to anyone who knows what may have happened to this man.
"Presently, he is sedated and we are unable to speak to him. We need to trace anyone who may have seen him in the area of Barrowby Road and Saint Augustin Way, Grantham, between 10.10pm and 10.20pm on Saturday night.
"We have not yet found his clothing and I would appreciate it if residents and businesses in the area would check their properties and gardens for any discarded clothing."