CAIRO: Egypt's aviation minister said that a terrorist attack was more likely to have taken down the missing EgyptAir aircraft early Thursday morning than a technical failure.

There were no known security concerns about passengers aboard the missing plane but further checks are underway, he told a news conference.

The EgyptAir flight from Paris to Cairo with 66 passengers and crew on board crashed in the Mediterranean Sea, Egyptian aviation officials said.

The minister said however that it was still too early to draw any conclusions as to the cause of the plane's disappearance.

EgyptAir Flight 804 was lost from radar at 2:45am local time when it was flying at 37,000 feet, the airline said.

It said the Airbus A320 had vanished 10 miles after it entered Egyptian airspace, around 280km off the country's coastline north of the Mediterranean port city of Alexandria.

Egypt's state news agency quoted Prime Minister Sherif Ismail as saying he can't “rule out” any possibility when asked whether a terrorist attack is behind the missing plane. He said there was no “distress call” but there was a “signal” received from the plane.

The aviation officials later said the plane crashed and that a search for debris was now underway.

The “possibility that the plane crashed has been confirmed,” as the plane hasn't landed in any of the nearby airports, said the officials, who spoke on condition of anonymity because they were not authorised to speak to the media.

The official said a signal had been picked up from the plane two hours after it disappeared from radar, thought to have been an emergency beacon.

Egyptian military aircraft and navy ships were taking part in a search operation off Egypt's Mediterranean coast to locate the plane. The plane was carrying 56 passengers, including one child and two babies, and 10 crew members. The pilot had 6,000 flight hours.

EgyptAir later said those on board included 15 French passengers, 30 Egyptians, one Briton, two Iraqis, one Kuwaiti, one Saudi, one Sudanese, one Chadian, one Portuguese, one Belgian, one Algerian and one Canadian. Earlier, the airline said 69 people were on board.

Relatives of passengers on the vanished EgyptAir flight have started arriving at Charles de Gaulle Airport outside Paris, where their loved ones boarded the aircraft.

The Airbus A320 most likely crashed into the sea, Ihab Raslan, a spokesman for the Egyptian civil aviation agency, told SkyNews Arabia.

Airbus is aware of the disappearance, but “we have no official information at this stage of the certitude of an accident,” the company's spokesman Jacques Rocca said.

The Paris airport authority and the French civil aviation authority would not immediately comment.

Azerbaijan plane crashes in Afghanistan, 7 dead

A US military spokesman in Afghanistan says seven people were killed when a plane belonging to Silk Way Airlines of Azerbaijan crashed in the country's south.

He said Thursday the plane had been carrying nine people when it crashed on take-off from Camp Dwyer, a military airport in Helmand province, a day earlier.

"Survivors were flown to Kandahar Airfield for treatment. The passengers are believed to be eastern European," the spokesman stated.

There was “no military involvement” in the crash, he says, adding that one of the plane's wings clipped the runway as it was taking off at 2.30 pm local time.

Representative of Silk War Airlines in Afghanistan could not be immediately reached for comment.

An EgyptAir plane was hijacked and diverted to Cyprus in March. A man who admitted to the hijacking and is described by Cypriot authorities as “psychologically unstable” is in custody in Cyprus.

The incident renewed security concerns months after a Russian passenger plane was blown out of the sky over the Sinai Peninsula. The Russian plane crashed in Sinai on Oct 31, killing all 224 people on board.

Moscow said it was brought down by an explosive device, and a local branch of the militant Islamic State (IS) group has claimed responsibility for planting it.

In 1999, EgyptAir Flight 1990 crashed into the Atlantic Ocean near the Massachusetts island of Nantucket, killing all 217 people aboard, US investigators filed a final report that concluded its co-pilot switched off the autopilot and pointed the Boeing 767 downward. But Egyptian officials rejected the notion of suicide altogether, insisting some mechanical reason caused the crash.