A device discovered in the bathroom of an Air France flight was a fake bomb, the airline’s chief executive officer has revealed.

The Boeing 777 was heading to Charles de Gaulle airport in Paris from Mauritius when its pilots requested an emergency landing early on Sunday, December 20, 2015 in the Kenyan city of Mombasa.

Frederic Gagey, the head of the airline, said the device was made of cardboard, paper and a household timer.

In a news conference in Paris, Mr Gagey congratulated the crew for their cool-headed reaction to divert the plane. He said the object ‘did not contain explosives’.

Mr Gagey says a safety check was carried out in the bathroom before the flight. He says passengers are checked, and sometimes double-checked on flights, and denied any security failure in the flight Sunday.

Six passengers were being questioned over the device, a police official said.

The plane was carrying 459 passengers and 14 crew members on board and had left Mauritius at 9pm. All passengers were safely evacuated and the device was taken out.

A passenger who spoke to journalists after leaving the plane in Mombasa described the emergency landing.

‘The plane just went down slowly, slowly, slowly, so we just realised probably something was wrong,’ said Benoit Lucchini, from Paris.

‘The personnel of Air France was just great, they were just wonderful. So they keep everybody calm. We did not know what was happening,’ said Mr Lucchini.

France has been under a state of emergency since the November 13 attacks in Paris that left 130 people dead.

The Islamic State group has claimed responsibility for that and the October 31 crash of a Russian passenger plane in the Sinai desert that killed all 224 people aboard. Moscow has said that the crash was caused by a bomb on the plane.

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