VIGILANTES could be to blame for setting fire to a barn belonging to a dairy farmer accused of sexually assaulting seven boys.

Up to 100 tons of hay bales were engulfed in flames as a blaze ripped through a barn on the Hilperton farm of 43-year-old Gordon Guley.

A tractor and trailer were destroyed as the fire swept through the building at Whaddon Farm in a matter of hours on Monday night, causing damage running into thousands of pounds.

Police are treating the blaze as arson despite fire investigators being unable to pinpoint whether the fire was started deliberately or accidentally.

A revenge motive is one of several options being examined by police. Detectives confirmed they are "keeping an open mind".

A second suspected arson at a Trowbridge farm earlier in the day is also under investigation with police making an arrest on Wednesday.

Guley faces 13 charges of sexually assaulting seven boys and a court case is underway.

Some of the sex attack allegations date back to the mid-1970s with charges stretching over a 22-year timespan. One of the alleged victims is still under the age of 18.

Guley, who lives at the Hilperton farm, has not entered a plea to any of the sex charges and the case is next before Trowbridge magistrates in September.

Det Con Neil Le-Maire, of Trowbridge CID, said police were looking at all possibilities in relation to the fire.

"We have to be open minded about it, taking in all eventualities, and we are going to make further inquiries.

"There is nothing linking the two fires apart from the fact there were two barn fires very close together on the same day. We are appealing for witnesses to both."

The detective tasked with investigating the sex claims against Guley is not in the team of officers working on the suspected arson.

Fire crews from Trowbridge, Bradford on Avon and Westbury were scrambled to the barn blaze at 11.30pm on Monday, battling with the flames into the early hours.

Crews were on-site until 8pm the following night as they guarded nearby farm buildings and waited for the fire to die out.

A Wiltshire Fire Brigade spokesman, who was one of the firefighters in the response crew, said: "There is no way to determine what or how the fire started.

"The barn was burnt to the ground. It was an intense fire 100 tons of hay went up quite quickly.

"It has been logged as cause unknown."

Fire-vandals are another motive detectives will focus their inquiries on, with a hay barn being torched at Paxcroft Mead just nine hours before the Hilperton blaze.

Fire crews from Trowbridge and Bradford on Avon were tasked to Lacock Gardens at 2.30pm, to find a barn used to store 30 tons of hay well alight. Police believe a discarded cigarette could have been the cause with total damage topping £9,000.

A 21-year-old Trowbridge man was arrested on Wednesday on suspicion of arson but later released on police bail.

Detectives quizzed the arson suspect about the Whaddon Farm fire but no separate arrest was made.

A Wiltshire Police spokesman said the force condemn vigilantism in the strongest terms.

He said: "Taking the law into your own hands is breaking the law yourself. There is a correct legal process.

"People are totally discouraged from taking their own action. There is no justification for it.

"With vigilantism innocent people may become involved. We condemn vigilantism extremely strongly."