Melanie Eversley

USA TODAY

An EgyptAir flight on its way to Cairo from Paris disappeared from radar Wednesday night, according to a tweet from the airline.

"An informed source at Egyptair stated that Flight no MS804, which departed Paris at 23:09 (CEST), heading to Cairo has disappeared from radar," the tweet read.

There were 56 passengers on board the Airbus A320 and 10 crew members, the airline said via Twitter. That number included two babies and a child, the airline said.

The families of the passengers were gathering at Cairo International Airport, where the airline was providing doctors, translators and other support and services. Several distressed family members collapsed at the airport, according to the Associated Press.

The aircraft disappeared after entering Egyptian airspace, according to EgyptAir. It vanished over the Mediterranean Sea at 37,000 feet, according to flight tracking services and EgyptAir.

Greek traffic controllers notified the airline that they'd lost contact with the plane, Ehab Mohy el-Deen, the head of Egypt's navigation agency, told The New York Times.

"They did not radio for help or lose altitude," he told the news organization. "They just vanished."

The aircraft most likely crashed into the sea, Ihab Raslan, a spokesman for the Egyptian civil aviation authority, told SkyNews Arabia.

EgyptAir listed the nationalities of the passengers as: 30 Egyptians, 15 French, two Iraqis and one each from Sudan, Chad, Portugal, Algeria, Canada, Great Britain, Belgium, Kuwait and Saudi Arabia.

The three-and-a-half hour flight left at 11:21 p.m. Paris time, more than half an hour after its scheduled departure of 10:45 p.m., according to the Flight Aware website. It was expected to arrive in Cairo at 2:55 a.m., 15 minutes after its scheduled arrival of 2:40 a.m., according to Flight Aware.

The airline said it would provide more details as they become available.

Back in March, EgyptAir Flight 181 en route to Cyprus was hijacked by a passenger claiming to be wearing a suicide belt. The hijacker surrendered at Larnaca International Airport in Cyprus and all passengers were released safely. No one was hurt in the incident, which Cypriot authorities said was not terrorism related.

EgyptAir operates from a hub at Cairo International Airport and is based in Heliopolis, Egypt. It offers passenger and freight services to more than 75 destinations.

On Wednesday, Secretary of State John Kerry traveled to Cairo and met with Egyptian President Abdel Fattah al-Sisi to discuss "a range of bilateral and regional issues," according to the State Department. The stop is part of a six-nation trip.

There are a number of terrorism organizations operating in Egypt, according to the State Department.

In January, Islamic State claimed responsibility for an attack on a hotel near the Pyramids of Giza, near Cairo. No one was hurt in the attack.

EgyptAir flight missing: What we know now

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