POLICE investigating a fire at a doctors' surgery in Darlington say the blaze was started accidentally.

Emergency services were called to the fire at the Carmel practice in Nunnery Lane shortly before 4am on August 30 and considerable damage was caused to the roof.

"Two similar incidents in other locations in the town on Sunday morning – at the Town Hall in Feethams and a building used by social services in Northgate – have been confirmed as arson with police believing the two may be linked," a spokesman for Durham Police said. "Enquiries have been taking place over the last week to establish whether the surgery fire was also suspicious, but a forensic investigation has now found the cause was an internal electrical fault.

"Police are continuing to appeal for two potential witnesses to come forward who may have information relating to the two arsons. 

"The male and female were seen walking from the area of the River Skerne through the cut under the canopy of the Town Hall towards the Dolphin Centre around 0120am on Sunday, August 30."

Anyone with information is asked to contact Darlington CID via 101.