LONDON - A private detective, who allegedly disappeared after being paid to search for missing British girl Madeleine McCann, and is wanted in the United States, was arrested in England, reports said Wednesday.

The British national, wanted by the FBI over an alleged fraud unrelated to the search for Madeleine, was arrested in Oxford in south England late Tuesday over an unpaid hotel bill, according to The Sun newspaper.

"We arrested a 48-year-old man yesterday morning at the Old Bank Hotel in Oxford. It was a discrepancy over his hotel bill," Thames Valley Police said, without confirming his identity.

The man's US company was paid 300,000 pounds (S$689,130) in 2008 to carry out detective work on possible sightings of Madeleine, but he disappeared and the contract was dropped because of lack of progress, reports said.

Thousands of Britons have donated money to a fund to help find the missing girl in a worldwide campaign.

The US-based businessman, whose company headquarters is in Washington, is wanted for allegedly defrauding a law firm of 1.2 million pounds, reports said.

Madeleine was nearly four when she went missing from her family's holiday apartment in Portugal on May 3, 2007 while her parents dined with friends nearby.

Despite a massive investigation by Portuguese and British police and huge publicity worldwide, she has not been found.

Portuguese police are no longer investigating the case but investigators acting on her parents' behalf are still looking for Madeleine and appealing to the public for information.

A spokesman for the McCann family said their association with the security consultant ended "well over a year ago."

"Given that an arrest has been made it would be inappropriate for us to comment," he said.