Search teams in late August located the flight data and cockpit voice recorders on the Yemenia Airlines Airbus A310 that crashed off the Comoros islands on June 30, killing 152 people.

The so-called 'black boxes' were located after a week of search led by a specially-equipped French vessel in the Indian Ocean in a zone where the average depth is estimated at 3,600 feet.

The causes of the crash of the plane, which was carrying mainly passengers of Comoran origin living in France, remain unknown. The plane plunged into the Indian Ocean as it was trying to land in Moroni. The sole survivor was Bahia Bakari, a 13-year-old girl who lost her mother in the crash and clung to a floating piece of debris for eight hours before being rescued.

Meanwhile, Agence France Presse reported that French investigators have evidence that the crash of a Yemenia flight was caused by pilot error, quoting two un-named French officials.

The Yemenia flight from France plunged into the Indian Ocean shortly after beginning its descent towards the Comoros.

"It seems there was pilot error," one French official told AFP, speaking on condition of anonymity because the French accident inquiry has yet to release formal conclusions. A second official separately confirmed the assumption.

Previously some French officials had suggested that the plane was not safe, but no official explanation for the accident has been given.

The Airbus A310's recorders were shipped to France where they are being examined by the French air accident investigation agency, the BEA.

The BEA is overseeing the technical side of the investigation on behalf of an investigation panel comprising officials from France, Yemen and the Comoros.