Oxford United are reeling from a double whammy - they are the first Football League club to be relegated and now face a repair bill of up to £60,000 following an arson attack at their new stadium.

A last-minute winner for Oldham Athletic at the Manor Ground on Saturday confirmed the drop to the Third Division.

This followed close on the heels of the fire at the £15m all-seater Minchery Farm stadium, which police believe was started by children early on Friday evening.

Club owner Firoz Kassam reassured fans that the fire would not stop the stadium being ready in time for the new season.

He said: "It's obviously very disappointing and it's unfortunate that it had to happen at this time. I have been on site and there is substantial damage but there will be no delays in the building programme. The club has got over worse things than this."

Police said the fire started in the main entrance of the partly built structure off Grenoble Road. Vandals are believed to have broken in through the outer security fence, slipped past the site's 24-hour security guards and forced open a door leading to the main stand.

They set fire to building equipment including boarding and insulation material, which created huge clouds of black smoke. Crews quickly put out the fire.

The bill for the damage was put between £20,000 and £60,000. Police forensic teams spent Saturday combing the site.

A member of the public called police on Friday evening, before the fire broke out, and said he had seen children playing inside the stadium.

Det Insp Paul Church said: "Although this inquiry is in its very early stages, we are aware that the land surrounding the stadium is often used by children as a play area. They may have seen something that could prove vital in this investigation. I would urge them - or anybody who was in the area at the time and saw anything suspicious - to contact us immediately."

Leslie Belcher, 40, a plasterer, of Acacia Avenue, Blackbird Leys, said: "I saw the smoke from my kitchen window and ran out to see what was happening. There were flames coming out of the glass entrance and really thick smoke pouring out.

"There was so much smoke I couldn't really see where it had started."

Last month, Oxford United struck a three-way deal with the city council and local landowner Les Wells which meant work to complete the stadium in time for next season could continue.

Martin Brodetsky, spokesman for campaign group Fighting for Oxford United's Life (Foul), said: "It does not look to me as though it was too sinister. I don't believe someone is trying to stop the development."

Tony Stockford, city councillor for Blackbird Leys, condemned the arson attack. He said: "There is no great opposition to the stadium here. I think most people just want to see it completed now."

Anyone with any information about the fire should contact police on 01865 266333 or Crimestoppers on 0800 555 111.

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