Defense lawyers for Dominique Strauss-Kahn are alleging that the hotel maid who accused him of a sex attack has "credibility" problems.
In a letter to Manhattan District Attorney Cyrus Vance, the lawyers said they now have "substantial information" that could derail the prosecution's case.
Defense lawyers Benjamin Brafman and William Taylor declined to give further details. The maid's attorneys did not return calls seeking comment.
"We could now release substantial information that in our view would seriously undermine the quality of this prosecution and also gravely undermine the credibility of the complainant in this case," the lawyers wrote.
Assistant DA Joan Illuzzi-Orbon said in a response letter that prosecutors were "troubled that you chose to inject into the public record your claim that you possess information that might negatively impact the case and 'gravely' undermine the credibility of the victim."
"We are aware of no such information," she added. "If you really do possess the kind of information you suggest that you do, we trust you will forward it immediately to the District Attorney's Office."
NYPD Commissioner Ray Kelly has called the woman's story "credible." Sources familiar with the case also say DNA found on the maid's shirt matches a DNA sample from Strauss-Kahn.
Strauss-Kahn is accused of attempting to rape the maid in the Sofitel hotel.
The allegations about the maid's story were raised in a broader letter where defense lawyers complained about leaks to the news media from inside the investigation.
The lawyers complained police are providing reporters with information about the timeline of the alleged attack and results of "scientific tests" that in their view could prejudice a jury.
The lawyers said they would consider complaining directly to the court if the leaks don't stop.
Meanwhile, the alleged victim has hired two more lawyers to assist her.
Veteran civil rights lawyer Norman Siegal and former federal prosecutor Kenneth Thompson will now team up with attorney Jeffrey Shapiro amid the intense scrutiny the case is getting.