At 12.16am on Thursday (28) one crew from Dogsthorpe and one crew from Stanground were called to a fire on Lincoln Road in Millfield, Peterborough.
Firefighters arrived to find a fire on the first floor of a three storey building. All occupants were safely evacuated before the crews arrived.
Using breathing apparatus the crews extinguished the fire using a hose reel and returned to their stations by 1.15am.
The cause of the fire was deliberate. Anyone with information should contact police by visiting www.cambs.police.uk to submit an online report or call Crimestoppers on 0800 555111.