French soldiers patrol at Charles de Gaulle airport, outside of Paris, Friday, May 20, 2016. The search continued on Friday for missing EgyptAir flight 804, which disappeared from the radar while carrying... (Associated Press) 
 
 CAIRO (AP) — Smoke was detected in multiple places on EgyptAir flight 804 moments before it plummeted into the Mediterranean, but the cause of the crash that killed all 66 on board remains unclear, the French air accident investigation agency said on Saturday. 
 
 Agency spokesman Sebastien Barthe told The Associated Press in Paris that the plane's automatic detection system sent messages indicating smoke a few minutes before the plane disappeared from radar while flying over the east Mediterranean early on Thursday morning. 
 
 The messages, he explained, "generally mean the start of a fire," but he added: "We are drawing no conclusions from this. Everything else is pure conjecture." 
 
 Looking for clues to whether terrorists may have brought down the Airbus A320, investigators have been poring over the passenger list and questioned ground crew members at Charles de Gaulle Airport in Paris, from which the plane took off. 
 
 The aircraft had been cruising normally in clear skies on a nighttime flight to Cairo early Thursday when it suddenly lurched left, then right, spun all the way around and plummeted 38,000 feet (11,582.4 meters) into the sea, never issuing a distress signal. 
 
 Search crews are scouring for further wreckage of the aircraft. Experts said answers will come only with an examination of the wreckage and the plane's cockpit voice and flight data recorders, commonly known as black boxes. 
 
 Planes and vessels from Egypt and five other countries — Greece, Britain, France, the United States and Cyprus — continued searching a wide area of the eastern Mediterranean on Saturday, a day after the Egyptian military found debris from the passenger jet in the sea 180 miles (290 kilometers) north of the Egyptian port city of Alexandria. 
 
 The waters in the area are 8,000 to 10,000 feet deep (2,440 to 3,050 meters), and the pings from the black boxes can be detected up to a depth of 20,000 feet (6 kilometers). 
 
 On Saturday, the Egyptian military released photographs of the debris from EgyptAir flight 804. The photos were posted on the Facebook page of the chief military spokesman. They appear to show the heavily-damaged remains of plane seats, life jackets — one of which was seemingly undamaged — and a scrap of cloth that looks to be part of a baby's purple and pink blanket or sleeping bag. 
 
 The spokesman's Facebook page later posted a brief video that showed more debris, including what appeared to be a piece of blue carpet, seat belts, a shoe and what looked like a woman's white handbag. The short clip opened with aerial footage of an unidentified navy ship followed by a speed boat with five service members aboard heading toward floating debris. 
 
 Egyptian authorities said they believe terrorism is a more likely explanation than equipment failure, and some aviation experts have said the erratic flight suggests a bomb blast or a struggle in the cockpit. But so far no hard evidence has emerged. 
 
 No militant group has claimed to have brought down the aircraft. That is a contrast to the downing of a Russian jet in October over Egypt's Sinai Peninsula that killed all 224 on board. In that case, the Islamic State group's branch in Sinai issued a claim of responsibility within hours. On Friday, IS issued a statement on clashes with the Egyptian military in Sinai, but said nothing about the plane crash. 
 
 Three European security officials said on Friday that the passenger manifest for Flight 804 contained no names on terrorism watch lists. The officials spoke on condition of anonymity because they were not authorized to discuss the investigation. The manifest was leaked online and has not been verified by the airline. 
 
 Further checks are being conducted on relatives of the passengers. 
 
 French aviation investigators have begun to check and question all baggage handlers, maintenance workers, gate agents and other ground crew members at Charles de Gaulle Airport who had a direct or indirect link to the plane before it took off, according to a French judicial official. The official was not authorized to discuss the investigation and spoke on condition of anonymity. 
 
 Whatever caused the aircraft to crash, the tragedy will most likely deepen Egypt's difficult predicament as it struggles to revive a battered economy and contain an increasingly resilient insurgency by Islamic militants. 
 
 In the five years since the country was first mired in turmoil caused by a popular uprising against longtime autocrat Hosni Mubarak, the lucrative tourism sector has been decimated, the value of the local currency has progressively fallen and domestic debt has mushroomed. 
 
 While the latest tragedy may not reflect directly on security at Egypt's airports, as the Russian jet crash did in October, the country's association with another air disaster will impact negatively on tourism and the flow of foreign investment. 
 
 In Paris, French Foreign Minister Jean-Marc Ayrault said Saturday that he and other officials — including representatives of Paris Aeroport, the French prosecutor, EgyptAir, and the Egyptian ambassador to Paris — had met with about 100 family members to express "our profound compassion" over the crash. 
 
 In a statement delivered to reporters following the meeting, he said: "All the hypotheses are being examined — none are being favored." 
 
 "In the name of France, once more, I am expressing my solidarity, but also our affection ... for all those people who learned that a loved one, or even an entire family, have drowned in the sea — and who want to know, to know to be able to grieve. It's a difficult moment, a painful moment. I wanted to say it again: We're on their side." 
 
 ___ 
 
 Satter reported from Paris. Associated Press writers Angela Charlton and Philippe Sotto in Paris and Paisley Dodds in London contributed to this report. ||||| Image copyright Egyptian Military/Reuters Image caption Debris from the plane has been recovered from the sea north of the Egyptian coast 
 
 A French naval ship specialising in underwater searches is on its way to help find the flight recorders of an EgyptAir plane that crashed last week. 
 
 On Thursday, Egypt's chief investigator said the search had narrowed to about 5km (3.1 miles) in the Mediterranean. 
 
 This was based on a signal from the plane's emergency beacon, but officials now say the signal was received on the day of the crash and is not new. 
 
 There were 66 people on board when the Airbus A320 crashed on 19 May. 
 
 The plane was flying overnight from Paris to Cairo when it vanished from Greek and Egyptian radar screens, apparently without having sent a distress call. 
 
 France's air accident investigation agency, the BEA, confirmed a naval oceanographic research ship, Laplace, is heading for the crash site. 
 
 In a statement, it said the ship was due to reach the crash area on Sunday or Monday, carrying a long-range acoustic system able to detect signals from the black box. 
 
 Image copyright AP Image caption Hundreds of people gathered in Cairo for a candlelit vigil for the victims on Thursday 
 
 Egypt's chief investigator, Ayman al-Moqadem, had said on Thursday that a signal detected was from a beacon situated in the rear of the cabin on the plane which transmits its location. 
 
 However, other officials on Friday told journalists that the signal was received on the day of the crash, and that there had been no other signals since. 
 
 "There has been nothing since day one," one official close to the investigation told Reuters. 
 
 On Thursday, hundreds of people gathered in Cairo for a candlelit vigil for the victims of the crash. 
 
 Among those on board MS804 were 30 Egyptians, 15 French citizens, two Iraqis, two Canadians and citizens from Algeria, Belgium, Britain, Chad, Portugal, Saudi Arabia and Sudan. 
 
 They included a boy and two babies as well as seven crew and three security staff. 
 
 Debris from the plane has been recovered from the sea, some 290km (180 miles) north of the Egyptian port city of Alexandria. 
 
 Media caption BBC transport correspondent Richard Westcott looks at the possible meaning of EgyptAir's smoke alerts 
 
 Egypt's president has said that "all scenarios are possible", but Civil Aviation Minister Sherif Fathy said last Friday that a terrorist attack was more likely than a technical failure. 
 
 Greece's defence minister said last week that, after leaving Greek airspace and before it disappeared from Greek radar, the plane abruptly turned 90 degrees left and then 360 degrees to the right, dropping from 11,300m (37,000 ft) to 4,600m (15,000ft) and then 3,000m (10,000ft). 
 
 The Aviation Herald also reported that the plane sent a series of warnings indicating that smoke had been detected on board three minutes before it disappeared. 
 
 However, an Egyptian aviation official denied the plane had deviated from its route, and that there had been reports of smoke. 
 
 Sources from Egypt's investigation team told Reuters and Associated Press on Friday that no emergency signals had been detected from the plane since the day it disappeared. Such signals are too weak to transmit from underwater, although signals from the flight recorders may yet be detected.
– Smoke was detected in multiple places on EgyptAir Flight 804 moments before it plummeted into the Mediterranean, but the cause of the crash that killed all 66 on board remains unclear, the French air accident investigation agency says. Agency spokesman Sebastien Barthe tells the AP that the plane's automatic detection system sent messages indicating smoke a few minutes before the plane disappeared from radar while flying over the eastern Mediterranean early on Thursday morning. The messages, he says, "generally mean the start of a fire," but he adds: "We are drawing no conclusions from this. Everything else is pure conjecture." The aircraft had been cruising normally in clear skies early Thursday when it suddenly lurched left, then right, spun all the way around, and plummeted 38,000 feet into the sea. Aviation experts have said the erratic flight suggests a bomb blast or a struggle in the cockpit. But so far no hard evidence has emerged. Search crews found floating debris and human remains on Friday, and photos posted on the Facebook page of Egypt's chief military spokesman appear to show the remains of plane seats, life jackets, and a scrap of cloth that looks to be part of a baby's blanket. Search crews from Egypt and five other countries—Greece, Britain, France, the US, and Cyprus—are searching a wide area of the eastern Med for further wreckage.