Around 50 Britons were forced to spend the night in hotels after an Egypt-bound passenger plane was forced to make an unscheduled landing when a note containing a bomb threat was apparently found on board.
The EgyptAir jet, which had departed from London's Heathrow Airport, was carrying 251 passengers when it landed at Athens International Airport, officials said.
The request to land was made by the pilot of flight 778, bound for Cairo, and it arrived at 8.39pm local time (6.39pm GMT).
Police were last night checking the plane for explosives but it is not known if any were found.
An Athens International Airport spokeswoman said: "Everybody is safe and the aircraft landed safely."
The airport spokeswoman said she understood a piece of paper containing the word "bomb" had been found on the plane, causing the pilot to divert to Athens.
There were about 50 British people on the flight who spent the night in hotels in the Greek capital, the Foreign Office said.
A spokesman added: "We have made sure they are aware of the latest travel advice. Consular staff on the ground have made sure everyone is alright."
The Foreign Office has cautioned against "all but essential" travel to Cairo, Alexandria, Luxor and Suez.
A spokesman for British Midland International said its daily flight from Heathrow to Cairo was departing as normal at 9.15am.
The plane, carrying 137 passengers, is due to land at 4.10pm local time.
A spokesman said: "BMI passengers yesterday all safely left the airport terminal at Cairo after the flight arrived, and we expect the same situation today."
British Airways (BA) said it had changed the timings of Cairo flights to operate outside the curfew.
For example, today's 5pm flight from Heathrow will now leave at 7.30am tomorrow.
Even if a passenger's flight is operating, they can choose to change the date of travel, obtain a refund or use the value of the ticket towards a journey to another destination.
Passengers may also choose to travel to Sharm El Sheikh instead of the Egyptian capital.
A BA spokeswoman said the airline had chartered an aircraft to bring people who want to leave Cairo home to Gatwick today.