A 20-year-old has been arrested on suspicion of arson after a fire broke out in the communal area of a property.
East Sussex CID are investigating the blaze at 11.20pm on Saturday in Eversfield Place, St Leonards, a Sussex Police spokesman said.
He said fire crews contained the blaze and investigations continued this morning.
Four people were rescued from the property following the fire in the landing, East Sussex Fire and Rescue said.
Witnesses should call Sussex Police on 101.
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