An arsonist may be to blame for a fire at a block of flats in Hove.
Twenty people had to be put up in emergency accommodation after the fire on Monday afternoon.
Sussex Police said: “Police are treating a fire at a block of flats in Hove as suspicious.
“Officers were called to assist East Sussex Fire and Rescue Service at the building in Nevill Avenue at 1.52pm on Monday (21 December) and all occupants were evacuated.
“Significant damage was caused to the communal entrance of the property and the fire is being investigated as suspicious.
“East Sussex Fire and Rescue Service has arranged for the British Red Cross to provide emergency housing cover for residents while the investigation continues.”
Detective Sergeant Mors Lambert said: “This was a significant fire which, if it had not been put out, would have caused a serious danger to the occupants inside.
“We are investigating it as suspicious but we are confident that it was an isolated incident.”
Witnesses are urged to phone Sussex Police on 101 or email firstname.lastname@example.org.