Detectives are investigating claims that a 15-year-old girl was gang raped and sexually assaulted during a school trip to one of the country's leading theme parks.

The teenager claimed she was attacked during an outing to Alton Towers, Staffordshire, on Friday, July 8. Details of the allegations were revealed by Staffordshire Police only yesterday.

A gang of six youths, believed to be from another school, are said to have surrounded the teenager and taken her to a secluded area where she was attacked.

The teenager, from Coventry, had earlier had a disagreement with friends and walked off by herself.

She suffered a panic attack after the assault and was treated by medical staff at the theme park before returning home.

Detective Constable Steve Kirkham, from Staffordshire Police, said: "There were approximately 24,000 people at the theme park that day, many of whom would have travelled from all over the country.

"We are appealing for anyone who may have seen the girl, who is described as very petite with mid-brown coloured hair, or saw the youths, to contact us."

In a statement, Alton Towers said: "This matter was brought to the attention of police and the park over a week later, and there was no report made on the day to either Alton Towers security department or fully trained medical team.

"A girl was treated for the after-effects of drinking alcohol on that day, but no other injury was reported by her, or observed by our medical staff at the time.

"Alton Towers takes the health, safety and welfare of its staff and visitors very seriously and has an excellent relationship with emergency services in the area. Had such an incident been reported, we would have involved all the appropriate bodies as a matter of course immediately.

"Over two million guests visit the park every year without incident, and we are confident that Alton Towers is a safe, fun environment for children of all ages."

Neither the girl or the attackers were in school uniform on the day of the trip.

One of the youths was described as white, of skinny build, with very blond hair, a pale complexion, freckles and long eyelashes. He was wearing a blue T-shirt.

A second was slightly smaller in height, darkskinned and wearing a white T-shirt and tracksuit bottoms.

Anyone with any information can call Staffordshire Police on 01785 233839 or Crimestoppers anonymously on 0800 555 111.