Two arson attacks over the weekend badly damaged a derelict building on Luton Road, Dunstable.
The first attack was on Saturday at 3.18pm when Bedfordshire Fire and Rescue received reports of smoke seen coming from the derelict building opposite Cartpetright.
When firefighters from Dunstable Community Fire Station arrived just four minutes later they found a small fire in pallets on the first floor of the two storey building. They used a fire hose to put this fire out and the incident was closed at 3.33pm.
But at 3.42pm on Sunday they were called out again.
Two fire engines from Dunstable Community Fire Station attended within six minutes to put out another fire on the first floor of the derelict building using a fire hose.
Both fires are being treated as deliberate and police and the fire service are now investigating.
There were no casualties.