Three men and a woman are being questioned by detectives investigating a petrol bomb attack in Londonderry which left a man critically ill with 40% burns.
Thomas Curry, 46, is being treated at the Royal Victoria Hospital in Belfast after he was set on fire at his home. Two men smashed a window of his house and then fired the petrol bomb inside where he was sitting on a settee.
Police said they are treating the attack as attempted murder.
Mr Curry, who lived alone, was dragged from the flames by neighbours at Ben Varden Avenue, in the Waterside district, late on Friday night.
A spokesman for the PSNI said that three men, aged 20, 24 and 25, as well as a woman, aged 45, had been arrested for questioning.
Inspector Jon Burrows, area commander in Foyle, said the man was lucky to be alive.
"He was pulled from the property by two neighbours who risked their own lives. Contrast that with the actions of the two cowards who threw the petrol bomb. But for the actions of those neighbours this man could possibly have died," said Insp Burrows.