A HEAD teacher today blasted cold-hearted young arsonists after they were caught on camera setting fire to a climbing frame used by children at a special school.

Tullyallan School, in Salisbury Road, Darwen, installed CCTV last July after a previous deliberate fire and trouble from local youngsters causing a nuisance at night.

Ian Wilson, acting headteacher, spoke out after the equipment, donated by local fund-raisers four years ago, was set alight after being doused in pertol by two boys aged around 12.

It is unclear whether the school can afford repairs.

Lancashire's schools have suffered 86 serious fires since 2000 and a record 3,100 crimes were committed against them last year.

Schools in Blackburn and Hyndburn are targeted by firebugs more than in any other area of the county and the situation has prompted fire chiefs, politicians and head teachers to discuss ways of reducing attacks.

Tullyallan has 40 pupils from all over East Lancashire who have behavioural problems. The attack, which took place on Friday night and was only discovered on Monday morning, is the worst the school has suffered.

Descriptions of the boys have been issued as police attempt find who they are.

Detective Chief Inspector Neil Smith said: "We want the public's help in identifying and catching the two boys responsible for this attack."

Mr Wilson said he was "flabbergasted" at the '"cold-hearted calculation" of the arsonists.

Local councillors also spoke of their disgust and questioned how children so young had obtained petrol. They said parents must do more to control their children.

Mr Wilson said the school installed two external and one internal CCTV cameras after someone set fire to a door last year. There were also problems with youngsters lurking around the secluded grounds and being a nuisance at night, he said.

"We want to raise the profile of the school and let people know we have CCTV. Hopefully this will scare them off from doing this in the future.

"We came to school on Monday and saw the frame was burned. People were shocked when they saw the damage, but more shocked when they saw the video.

"One of the lads was lucky not to have been burned himself.

"We use the slide with primary-age children and it was donated from a local group. The school couldn't afford to install it."

Ward Coun Dave Hollins said he planned to visit the school to offer his help. "It's awful that two young kids like that have got involved in that," he said. "Where have they got the petrol from?"

Coun Paul Browne, who was on the board of governors at the school for 30 years until recently, said: "It is disgusting. For kids that age to do something like that is unbelievable. "

One of the boys was wearing a cream jacket, the other a dark coat. Both have short hair.

Anyone with information should call Darwen CID on 01254 353842 or Crimestoppers on 0800 555 111.