LONDON - MANCHESTER United fans called for an official investigation on Wednesday into ticket prices increases since the Premier League club was bought by American businessman Malcolm Glazer in 2005.

The Manchester United Supporters Trust, which opposed the takeover as Shareholders United and represents 34,000 fans, filed a complaint with the Office of Fair Trading.

The group claims the club's ticket pricing policy violates competition law, with some tickets rising by as much as 60 per cent.

'Over recent years we have seen unfair terms and huge ticket price rises imposed on supporters by club owners taking advantage of their loyalty,' MUST chief executive Duncan Drasdo said.

The complaint notes that United requires season ticket holders to purchase additional tickets for non-Premier League matches, including the FA Cup and Champions League.

Before the compulsory cup ticket plan was introduced in 2007, season tickets gave access only to league matches. The club responded to some of the fans' anger by exempting League Cup matches from 2008-09 season ticket packages.

Mr Drasdo said there is still an imbalance because the club has no obligation to supply tickets to bigger cup matches, while still forcing fans to pay to see low-key fixtures.

He said some season ticket holders were denied access to Old Trafford last season to see the Champions League semifinal against Barcelona - despite having to buy tickets for the earlier League Cup match against Coventry.

'For a long time Manchester United was by no means the worst offender having previously had an admirable policy of keeping prices relatively low despite the success of the club,' Mr Drasdo said. 'All that changed when the Glazers took over.

'However now, with the help of a team of eminent competition lawyers, economists and experts in sports law, we have been able to compile a comprehensive complaint based on Competition and Contract Law.' In that dossier, MUST claims that a season ticket that would have cost 532 pounds (S$1,222) in 2004-2005 now stands at 912 pounds - before cup matches are factored in. United made no comment on Wednesday.

Earlier this year, British sports minister Gerry Sutcliffe said United was 'pricing out' ordinary fans, but Sir Alex Ferguson, who has been manager for 22 years, hit back by branding the prices at rivals Arsenal and Chelsea as 'obscene.' -- AP