Two Paris-bound Air France airliners diverted after unspecified threats were made over the phone.
A bomb threat that forced a flight from Mauritius to Paris to make an emergency landing in Kenya was a “false alarm”, Air France said on Sunday.
The airliner’s chief executive Frederic Gagey said the suspicious device, which had been found in the lavatory on the plane, did not present any danger to its passengers.
“The object was not capable of causing an explosion,” Gagey told reporters.
“All the information we have at this stage shows that the object was not capable of causing an explosion that would damage the plane but was rather a mixture of cardboard, pieces of paper as well as a timer.”
Earlier on Sunday, Kenya’s Interior Minister Joseph Nkaissery said authorities were working with their French and Mauritian counterparts to determine the nature of the device.
Several passengers were questioned after the jet flying to Paris from Mauritius landed in the Kenyan coastal city of Mombasa.
The Boeing 777 landed at Moi International Airport before 1am local time (21:37 GMT). It was carrying 459 passengers and 14 crew members on board.
During the flight, a passenger noticed something in a lavatory that looked like “a stopwatch mounted on a box”, an official told the Associated Press news agency.
The passenger reported the device to the cabin crew, who informed the pilots, leading to the emergency landing.
The official said one of those being interrogated was the man who reported the device.
“It requested an emergency landing after a device suspected to be a bomb was discovered in the lavatory. An emergency was prepared and it landed safely and all passengers evacuated,” police spokesman Charles Owino told the AFP news agency.
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 of 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 Lucchini.
“So we secured the seat belt to land in Mombasa because we thought it was a technical problem, but actually it was not a technical problem. It was something in the toilet.”
The Indian Ocean island nation of Mauritius, which lies about 1,000km east of Madagascar, is a favourite vacation destination for French nationals.
France has been under a state of emergency since the November 13 attacks in Paris that killed 130 people.
The Islamic State of Iraq and the Levant (ISIL) group has claimed responsibility for that and the October 31 downing of a Russian passenger in the Sinai desert that killed all 224 people aboard.
Moscow has said the crash was caused by a bomb on the plane.
Two Air France flights from the US to Paris were diverted on November 18 after bomb threats were received. No bombs were found on the planes from Los Angeles and Washington DC.