Air France plane crash: French official confirms signals not from black box.

A French official on Tuesday ruled out earlier reports that signals for the Air France flight 447's black boxes have been detected.

Commander Christophe Prazuck told BBC Brasil that in the past days "various signals have been detected by the French marine but none of which are from the black boxes."

Prazuck said many signals were detected but upon closer examination, investigators found that they do not belong to the Air France jet that crashed into the Atlantic on June 1.

"Till this moment, the black boxes have neither been detected nor found", the commander said.

The two recorders are essential to help determine what happened to the crashed jet that plunged into the ocean killing all 228 people on board.

The black boxes' locator beacons, known as pingers, will emit signals for only another eight days. After that, it could become impossible to locate the black box flight recorders and discover what happened to the Airbus A330 which crashed approximately four hours after taking off from Rio en route for Paris.

Searchers have been combing an area with a radius of 50 miles in the hope of detecting signals from the boxes that can be heard only up to about two miles.

The Airbus A330 plane fell into the Atlantic after running into thunderstorms en route from Rio de Janeiro to Paris.