Owners of a former timber yard which was the scene of a major blaze had previously worked with firefighters to try to secure the site after fears of arson attacks had been raised.
Charles Taylor, a member of the trust which owns the site, said the former headquarters of CR Taylor Timber, in Station Sawmill, in Station Road, Denholme, had suffered vandalism in the weeks before a major blaze in the early hours of yesterday.
Crews from Illingworth, Bingley, Fairweather Green, Haworth and Keighley were called to the scene, along with specialist vehicles and equipment from Stanningley and Garforth, at about 3.40am yesterday, after an office block and storage shed caught fire.
The cause of the blaze was under investigation yesterday.
Mr Taylor, managing director of Taylor Timber, bought the Bradford branch of the former Denholme-based CR Taylor Timber, of which he was executive chairman, from the administrators when recession forced the long-established company into liquidation earlier this summer.
He said the trust that owns the site, which had planning permission for houses to be built there, was trying to sell it to a developer.
He said: “There had been a fire about two weeks ago in a different shed, but it was luckily put out, so I’ve been working with the fire brigade to try to find ways of making it safe and preventing it happening again.
“There’s been a problem with the local kids going in on their motorbikes.
“It’s just been a constant pain – the sooner we can make it unattractive to anyone like that, the better really.”
Mr Taylor said he had been left devastated by the fire. He added: “It’s where the business has been for 52 years. The shed that burned down is a historical building which we were wanting to take photos of before any houses were built or it was demolished.”
Watch commander Colin Pickles, of Illingworth fire station, said crews had visited the site to check its safety after residents had spoken of their concerns.
He said: “We met with residents in Denholme doing home fire safety checks and they voiced their concerns, so we came down to have a look at it and saw that people had been breaking in through the fences and had been vandalising the offices.”
He said firefighters had attended small fires in the last two weeks.
Nobody was injured in the fire, which destroyed an office block and one of the storage sheds.
Olwen Fletcher, owner of stables next to the site, said she had been worried a fire might break out. She added: “I come down two or three times a day and there’s always kids about playing.
“It was my biggest fear that would happen, but I could see that being the natural progression.”
Station commander Mick Davis, incident commander at the scene, said: “The three-storey block was fully destroyed but the crews worked hard to prevent it from spreading to a single-storey workshop next to the site and most of that has been saved.”