TEN fire crews battled to tackle a blaze that engulfed a building at a former mental asylum.And yesterday specialist officers were investigating whether the fire that gripped the medical superintendent's building at Severalls Hospital in Colchester might have been started deliberately.

TEN fire crews battled to tackle a blaze that engulfed a building at a former mental asylum.

And yesterday specialist officers were investigating whether the fire that gripped the medical superintendent's building at Severalls Hospital in Colchester might have been started deliberately.

Firefighters were called to the scene of the blaze at around 10.30pm on Wednesday, by which time it had been burning for some time.

Initially there were fears that the building – which had no electricity or gas supply – was occupied by homeless people.

Essex Ambulance Service was alerted to the incident by Essex Fire Service at 10.45pm last night.

Two ambulances and the incident support unit manager from headquarters attended the Rendezvous Point after concerns that there could have been people inside the property.

But searches later revealed that nobody was there by the time the emergency services arrived.

One of the ambulances was stood down, but the other resources remained at the scene to provide cover in case any of the firefighters suffered injury while tackling such a large blaze.

Crews from Colchester, Wivenhoe, Brightlingsea, Manningtree and Brentwood attended the fire.

Specialist equipment used included a rescue unit, an aerial ladder platform and the Essex Fire Service control unit.

Leading firefighter Stuart Hare, based at Colchester Fire Station, said: “It was one of the big ones. We were told that there could have been people inside.

“We had to wait for daybreak to conduct a proper search.

“It was one of those fires where you say to yourself 'Thank God' for your training, because it saved us.”

Ian Richards, of Save Severalls Group, said: “I saw the building on fire as I drove past. My first thought was that it was the hall there.

“It was very bad, but it could have been a lot worse. We have lost one of the best buildings on the site.

“The building was not wired up electrically and there was no gas supply.

“I think one of two things happened – either somebody deliberately flamed it or there have been dossers in there and a candle or something has been knocked over.”

A fire spokesman confirmed yesterday that an investigation into the blaze was underway.