The cause of a fire in the derelict St Edmund’s Hospital building is being investigated.
The fire broke out at about 5.30pm yesterday and three fire engines were called to the site, which is just off Wellingborough Road, Northampton.
Firefighters discovered waste loft insulation had caught light on the ground floor and put out the flames using a hose reel.
Officers from Northamptonshire Police also attended the scene and the fire service said the cause of the fire is now being looked into.