In Europe, seven passenger aircraft, two of which departed from the United Kingdom, were inspected following reports of a possible bomb threat.
As BBC sources at Rome’s Fiumicino Airport said, after landing in Rome two Ryanair aircraft (arriving from Dublin and Lisbon) were searched after anonymous messages were received, but no explosives were found.
The aircraft travelling from Dublin was escorted by Italian Air Force fighter jets until it landed. Aircraft checks also took place in Poland, Spain and Bulgaria.
Although no official link between these incidents has been confirmed, the relevant authorities in different countries will work together to determine whether this was a co-ordinated attack aimed at destabilising the situation in the airspace.
The UK government described the incidents as “malicious threat reports that turned out to be false”.
Aviation security expert Paul Mason noted that bomb threats against passenger aircraft “do not happen very often”, making the recent events “unusual”.
“It appears these threats were worded quite convincingly and involved many different airlines. That suggests this is targeted action by a particular actor, rather than a random coincidence of several malicious calls,” Mason told BBC Radio 5 Live.
He said there is “a whole range of procedures” that the flight crew and ground services must carry out to “assess how serious the threat is”.
Paul Mason added that if the threat level is assessed as sufficiently serious, the aircraft may be diverted to another airport. In some cases, the crew are not even told exactly what the ground services are dealing with.
In Rome, sources at Fiumicino Airport told the BBC that police bomb disposal officers carried out standard security procedures to ensure the safety of all passengers and crew members.
Spanish authorities also said no explosives were found on board a Ryanair aircraft that arrived from Manchester to Murcia (southern Spain).
One of the passengers later said she only learned about the bomb threat after the plane had landed.