(Bloomberg) -- Egyptian authorities said they discovereddebris, body parts and personal belongings from passengers of thedoomed EgyptAir plane that crashed in the Mediterranean Sea in theearly hours of Thursday, all but quashing any hope of survivorsamong the 66 people on board.

The search by Egyptian forces and supporting countries remainsin progress, the airline said in a statement. Among other piecesdiscovered were luggage and aircraft seats. No reference was madeto the search for the cockpit-voice and flight-data recorders,which could offer valuable clues about what downed the Airbus A320on its flight from Paris to Cairo.

Salvage teams from Greece and Egypt have been joined by Frenchinvestigators to find more debris as authorities seek to piecetogether what happened to the Airbus single-aisle jet. The flightlost contact in the middle of the night in the wider area of theStrabo trench in the so-called Hellenic Arc in the sea south ofGreece, where waters are as much as 3,000 meters (9,800 feet) deep.The debris was discovered about 290 kilometers (180 miles) north ofAlexandria, authorities said earlier.

Officials aren’t ruling out any possible cause for thedisappearance, including a deliberate act or malfunction, thoughEgyptian Minister of Aviation Sherif Fathy said thepossibility of a terrorist attack is higher than a technicalfailure. Flying at cruising altitude through clear skies, theAirbus jet made sudden movements before swooping into a steepdescent and losing contact with air-traffic control, accordingto Greek radar reports.

Pilots sent no emergency signal, and their final contact withcontrollers revealed no signs of distress. The lack ofcommunication points to a “brutal” event, said Jean-PaulTroadec, the former head of France’s BEA air-safety authority.

“Normally if there’s a technical problem with engines, or aproblem of pressurization, or something else, there are tools thatlet a pilot warn he’s got a problem,” Troadec said Friday in aninterview on French radio Europe1. “Nothing of the sorthappened.”

Black boxes

Salvage crews will focus on retrieving the flight and datarecorders, so-called black boxes that store key flight metrics andvoices and sounds from the cockpit that can help investigatorspinpoint the cause of a crash. The condition of the debris and theway it is scattered may also offer early clues about the possiblecause, with a wide field of small pieces pointing to a mid-airbreakup of the plane, while large chunks might suggest the aircrafthit the water largely intact.

Retrieving the black boxes from the ocean bed can be an arduousprocess, particularly in great depths. It took salvage crewsseveral years to locate and then pull up the devices from thedoomed Air France AF447 flight that went down in the Atlantic Oceanin 2009. The missing Malaysian Air MH370 still hasn’t been foundtwo years after it disappeared, with only some small pieces fromthe plane washed up thousands of miles from where crews continue tocomb the sea bed.

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The boxes, which are fortified and painted bright orange tofacilitate their retrieval, typically emit a ping for several weeksto lead salvage crews to their location.

EgyptAir investigators race against time, sea for evidence

Several factors come into play when searching for wreckage in anocean. Sea currents, weather and the speed at which the jet hitsthe water are some issues to be taken into consideration, said KenMathews, a former accident investigator who’s worked with the U.S.National Transportation Safety Board as well as its U.K. and NewZealand peers.

“If they narrow down the likely area, then it’s only a matter oftime,” Mathews said. “The Mediterranean is not a vast area, or sodeep as an ocean.”

Investigators focused on the last minutes of the flight, whichtook off at 11:09 p.m. in Paris with 56 passengers, 7 crew and 3security personnel. The aircraft, a modern single-aisle jetmanufactured in 2003, was traveling at cruising altitude beforedisappearing from radar off the Egyptian coast. French air safetyinvestigator BEA will dispatch three experts, accompanied by Airbustechnical adviser, to help with the search and retrieve thecockpit-voice and flight-data recorders.

While the cause of the incident hasn’t been identified, mid-airemergencies are rare, especially for a relatively new plane. Theweather in the area of the sea close to Egypt was also good, withno winds or clouds, the Hellenic National Meteorological Service inGreece said. The sudden disappearance of an airliner at cruisingaltitude and with no distress call from the pilot at least raisesquestions of foul play, said Paul Hayes, director of air safety atLondon-based Ascend, an aviation consultancy.

“It is our duty to know everything about the causes,” FrenchPresident Francois Hollande said at a press conference Thursday.“As soon as we know the truth, we’ll have to draw all conclusions,be it an accident or any other hypothesis,” includingterrorism.

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