Firefighters from Ramsey and St Ives were called to a fire in Ramsey on Wednesday.
One crew from Whittlesey, one crew from Ramsey, one crew from Chatteris and one crew from St Ives were called to a building fire in Factory Bank, Ramsey at around 7:30pm
Cambridgeshire fire and rescue spokesman said: "Crews arrived to find a derelict office building well alight. Firefighters used two hose reels and two jets to extinguish the fire before returning to their stations by 10.15pm."
The cause of the fire is unknown.