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Egyptair says that security scans on the aircraft took place prior to take-off from Paris. All employees of the airport and airline that could have had access to the plane or luggage prior to take-off are reportedly being questioned.
Investigators are examining CCTV footage from the airport in an attempt to identify those who had access to the plane while it was on the ground, police sources said.
“There is no confirmation that the airliner was downed by a terrorist attack, but the investigation is already under way just in case,” a source said. “They are looking for any sign of suspicious behaviour and checking people’s identities.”
Paris prosecutors have opened an investigation and no theories are being ruled out.
If terrorism is confirmed, the authorities will have serious questions to answer about security at the airport, which was stepped up after the Paris attacks in November, and further strengthened after suicide bombings at Brussels airport in March.