Smoking materials are thought to have caused a blaze at a house in Gainsborough.
Firefighters tackled the house fire in Noel Street at around 9.30pm on Wednesday night (18th July).
A spokesman for Lincolnshire Fire and Rescue said initial investigations suggested smoking materials were the source.
The fire ripped through a first floor bedroom at the property causing severe damage.
Heat and smoke damage was caused to the rest of the house.