UP to 15 squatters fled a fire at a derelict house in Bessborough Road, Harrow, that was spotted by a passing police officer.

The PC, who was on duty but has not been named, saw smoke emanating from the supposedly vacant detached three-storey home at number 79 9pm on Friday and raised the alarm.

Up until six years ago the property used to be a home for adults with learning disabilities run by Harrow Council and in 2010, Dipak Vithlani, of Northwood, was granted planning permission to turn the site into a 30-bed nursing home. 

He said he had just arrived back from being away at the weekend to find out there had been a fire but did not wish to add anything at this stage.

A Harrow Police spokesman said: "Officers evacuated 11 people believed to be squatters. Neighbouring properties were evacuated. There were no injuries and no arrests and the fire is non-suspicious."

London Fire Brigade put the total numbers of occupants who escaped as 15 and firefighters eventually extinguished the flames at 1am on Saturday morning although half the second floor was damaged and the roof was burned through.

Harrow Police had had to close off Bessborough Road between Lascelles Avenue and Kingsfield Road.

The cause of the blaze may be revealed today by fire investigators.

A Harrow Council spokesman said: "It used to be a residential facility for adults with learning disabilities. We sold it back in 2006."