MANCHESTER United have launched an investigation after a prankster tampered with a giant neon sign at the Old Trafford stadium to spell out a four-letter word.

The sign - which normally highlights the club's name - stand dozens of feet above Sir Matt Busby's statue.

The sign was corrected after the M.E.N. alerted the club about the vandalism.

Joke

Manchester United played down suggestions the prank was connected to anger over the club's recent takeover. They said it was a workman's joke.

A spokesman said: "We have had contractors in doing work on the stadium. It seems someone has messed with plugs at the back of the lights as a prank.

"We would like to apologise to anyone that took offence - the sign now proudly says Manchester United again."