French prosecutors said they were looking into claims that Dominique Strauss-Kahn took part in a gang rape at a Washington hotel, but the disgraced former IMF chief denied any wrongdoing.
Strauss-Kahn, two businessmen and a police chief had already been charged with "aggravated pimping in an organised gang" for allegedly organising a prostitution ring for orgies in France, the United States and elsewhere.
On Friday, a spokesman for the state prosecutor's office in the northern French city of Lille said that investigating magistrates had submitted new evidence that could implicate the men in a sexual assault in Washington.
News that makes sense
Your trusted source for staying up-to-date with the world around you. Get free daily news updates and analysis, straight to your inbox.
"The Lille prosecutor was presented by the magistrates charged with investigating the 'Carlton affair' with a notice to make known, for whatever useful purpose, evidence of gang rape," the spokesman said.
It was understood that the magistrates have not requested they be permitted to formally investigate an alleged rape, but for official purposes have warned the prosecutor that some testimony points in that direction.
Following such a notice, a prosecutor can either throw out the allegation or order a preliminary inquiry to establish if there is enough prima facie evidence to expand the original probe to include the newer charge.
"This notice is being examined," the prosecution spokesman said.
Strauss-Kahn's lawyers denounced the claims as a "lynching," and contested the "contradictory" testimony from two escorts suggesting their client took part in the rape.
The former IMF chief "absolutely contests having committed the slightest act of violence of any nature whatsoever," his lawyers Henri Leclerc, Frederique Baulieu and Richard Malka said in a statement.
"Distorted information, manipulation and a desire for a lynching cannot forever be a substitute for reality."
The lawyers also pointed to the timing of the release of the testimony, which dates from late March, just two days ahead of Sunday's hotly contested run-off in the French presidential election.
Strauss-Kahn had once been the frontrunner to lead the Socialist Party against incumbent Nicolas Sarkozy in the vote. The Socialists instead chose Francois Hollande, who is tipped to win on Sunday.
The notice is based on testimony from a Belgian sex worker who alleged she was forced to take part in sex acts against her will at a party attended by Strauss-Kahn and his friends at the W Hotel in Washington in December 2010.
Another Belgian escort present at the sex party partially confirmed her statement, but neither has sought to press charges. Washington police said it had no report of such an incident.
"We've had no report of a sexual assault for December 2010 at the W Hotel," police spokesman Officer Hugh Carew told AFP, adding that he was unaware of any complaint against Strauss-Kahn in Washington as a whole.
Strauss-Kahn has admitted he had a free-wheeling sexual lifestyle when he was managing director of the Washington-based International Monetary Fund, but has fiercely denied that he was ever violent toward a partner.
Strauss-Kahn was arrested in New York a year ago after a hotel maid alleged he had subjected her to a brutal sexual assault in his hotel suite.
The criminal case collapsed amid doubts about the alleged victim's testimony, but she is still pursuing a civil suit against him, and Strauss-Kahn found himself implicated in other scandals upon his return to France.
The so-called "Carlton affair" centres around allegations that business leaders and police officials in the northern city of Lille operated a vice ring supplying girls for sex parties, including at Lille's Carlton Hotel.
The same ring allegedly provided women for orgies attended by Strauss-Kahn in Paris, Washington and European cities, and investigators believe they can prove the former finance minister committed crimes.
Paying for sex is not illegal in France, but profiting from an organised vice ring is, and Strauss-Kahn could face a lengthy jail term.
