What happened inside the Emirates aircraft was described by passengers of flight EK 209 which was bound for New York but returned to Athens shortly before 10:00 in the evening.
"We were very worried. We had no information when we realised that the plane was returning to Athens and when they cut off our internet so that we could not read and learn the news," said a Greek passenger to Proto Thema.
"Then we knew something was up. Those sitting at the windows saw two fighter planes accompanying us. The only thing we understood was that we were going back, we were all calm even though we had no information," he added.
"While the plane was approximately over Italy we were informed that the plane was turning back because there was a problem with French airspace. That's all we knew. We asked the staff to give us some information but they couldn't tell us much," said another passenger.
"Those of us who had boarded from Athens got out, those who were from Dubai remained on the plane to undergo a further check. We got off the plane and were scrutinised again," said another passenger.
A foreign passenger noted that the order given to passengers when the plane taxied was to get up and leave the aircraft. Only those who had entered from Athens got off and all the rest to remain in their seats.
The decision to call back one of the planes and ground the other came as a request from US authorities who informed the Greek police about a "suspicious" passenger, according to Greek media and police sources.
However, the Greek authorities refused to confirm the exact source or nature of the American request.
The aircraft was traveling over Sardinia when the request to return to Eleftherios Venizelos Airport was made.
France and Italy both refused to allow the aircraft to land.
The flight, which had been on route to Newark airport, returned safely to Athens two hours after taking off, according to officials.
Flight 209 was escorted back through Greek airspace by two Greek air force F-16s, according to military officials.
According to Greek police, nothing suspicious was found on the aircraft following a search.
The aircraft was reportedly carrying 228 passengers and 18 crew members, according to The Daily Mirror.
Meanwhile passengers on the Dubai bound flight were searching thoroughly after disembarking as they were forced to take off their shoes and other items at the terminal, according to reports.
According to ABC, Greek police confirmed that their concerns about a suspicious passenger was not confirmed by their inspections.
The flight then finally took off for Dubai hours later.
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