Arsonists set fire to a derelict building in Wisbech yesterday afternoon, Tuesday May 9.
Crews from Wisbech, March, Whittlesey and Huntingdon, along with crews from Kings Lynn in Norfolk, attended the scene in Meadowgate Lane at 4.25pm.
Firefighters arrived to find a well-developed fire in a derelict property.
Flames and smoke were spreading through the roof.
Firefighters tackled the fire from the outside using jets as the roof collapsed.
They extinguished the fire and returned to their stations by 8.45pm.
The cause of the fire was deliberate.
Anyone with information should contact police on 101 or Crimestoppers on 0800 555111.