PARIS — French military ships searching for the black boxes of Flight 447 have detected sounds in the Atlantic depths but not from the Air France plane's flight recorders.

An official and French investigators denied a report on the Web site of the French newspaper Le Monde that French ships had picked up a signal from the black boxes.

The two recorders, key to helping determine what happened to the plane which plunged into the ocean May 31, will only emit signals for another eight days or so.

French vessels in the search area have picked up noises regularly, but subsequent investigation has revealed no link to the black boxes.

The French air accident investigation agency, BEA, said Tuesday that "no signals transmitted by the flight recorders' locator beacons have been validated up to now."