Updated: May 20, 2016 10:46 AM ET | Originally published: May 20, 2016 3:14 AM EDT

The Egyptian army says it has discovered debris it believes is from EgyptAir Flight MS 804, which went missing from radar screens in the early hours Thursday.

The Associated Press (AP) reports that Greece’s defense minister says authorities were told Egyptian officials had spotted body parts, seats and luggage during their hunt for the jet. Minister Panos Kammenos said the discovery was found slightly to the south of where the aircraft vanished. The European Space Agency also said Friday that satellites had spotted an oil slick in the region where the plane was believed to have disappeared.

A satellite image provided by the European Space Agency of a slick in the eastern Mediterranean Sea, about 40 km southeast of the last known location of EgyptAir flight MS804, May 20, 2016.

A large-scale search-and-rescue operation has been underway for the missing flight, which was carrying 66 passengers and crew and was en route from Paris to Cairo. It is believed to have crashed into the Mediterranean Sea somewhere between Greece and the Egyptian coastline. The cause of the disaster remains unknown.

The BBC reports that the Greek, Egyptian, French and British militaries are all involved in the search for the Airbus A320 aircraft.

Authorities have said the pilot did not send out a distress call, and that the plane appeared to be flying untroubled at a cruising altitude of about 37,000 ft. before beginning a rapid downward spiral toward the water.

The lack of other plausible explanations for the apparent crash has led many to conclude that the plane must have been the target of a terrorist attack. Egypt’s Minister Civil Aviation Sherif Fathi said in a press conference in Cairo the chances of the crash being caused by terrorism were “higher than the possibility of a technical failure,” the AP reports.

But French Foreign Minister Jean-Marc Ayrault refused to draw conclusions. “We’re looking at all possibilities, but none is being favored over the others because we have absolutely no indication on the causes [of the crash],” he said Friday, reports Agence France-Presse.

Details have begun to emerge about the seven EgyptAir crew members on the flight (there were also three security guards on board). The airline named the captain as Mohamed Said Shoukair, who had some 6,275 flying hours under his belt, including more than 2,000 hours flying the A320, the Guardian reports. It also named co-pilot Mohamed Mamdouh Ahmed Assem, who had a total of 2,766 flying hours, and head flight attendant Mirvat Zaharia Zaki Mohamed.

There were 56 passengers on board flight MS 804, including 30 Egyptians, 15 French nationals, two Iraqis, one person from each of Algeria, Belgium, Canada, Chad, Kuwait, Portugal, Saudi Arabia and Sudan and a British-Australian dual citizen.

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Write to Simon Lewis at simon_daniel.lewis@timeasia.com.

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