At Least 18 European Flights Hit by Bomb Threats in One Day as Expert Cites 'Deliberate Act'

At least 18 commercial flights across Europe received bomb threats on Thursday, forcing diversions, emergency landings and fighter jet escorts, though authorities reported no explosives discovered on any of the aircraft and all of the threats appeared to be hoaxes.

The incidents pushed the number of journeys affected by similar threats this week to at least 25, meaning significant disruption for thousands of passengers and raising concerns about a possible coordinated effort to impact travel on the continent. British authorities had already dismissed threats against about seven flights earlier in the week as hoaxes. It remains unclear who is behind the threats, and no authorities have confirmed a link between any of them.

In the most dramatic case on Thursday, an Aer Lingus flight from Dublin to Rome was diverted to a military air base in Evreux, in western France, because of a bomb threat, according to the office of French Prime Minister Sebastien Lecornu. The flight landed safely and all 151 passengers and six crew members deplaned while military bomb defusal teams examined the plane. Flight tracking sites showed the jet turning sharply off its trajectory and making several loops before heading toward Evreux.

Elsewhere, a Finnair flight from Helsinki to Rome was escorted to the Italian capital by a fighter jet and checked by bomb disposal experts, according to Italy's national news agency ANSA, while Rome's Leonardo Da Vinci Airport stopped flights for 30 minutes. A Wizz Air flight from Milan Malpensa to Warsaw was rerouted to Vienna after receiving a threat, a LOT Polish Airlines flight from Warsaw landed safely in Brussels following security warnings, and three Ryanair flights bound for Sofia made emergency landings in Bulgaria, two in the capital and one in Plovdiv. Officials in Prague said threats were issued against four flights headed to the Czech capital, three flights were affected at Madrid's Barajas airport, and two more flights landed safely at Milan's Malpensa after what ANSA described as bomb alerts. In each case, checks by security forces found no explosives or suspicious items.

Some of the threats have been sent to airlines by email, but the nature of all of the messages has not been confirmed. The British government described the incidents in a statement on Tuesday as hoaxes and stressed that the U.K. had "one of the most robust aviation security systems in the world."

Air transport security expert Paul Mason told the BBC that threats to passenger planes "don't happen that frequently," making this week's spate of incidents unusual. "It sounds like they've been made in a credible manner across a broad range of airlines," he said. "That would suggest to me that it's been a very deliberate act by a typical actor rather than a load of coincidental, malicious calls." He noted that airline crews and ground staff go through extensive processes to validate the credibility of any threat.

While no individual or group has claimed responsibility and no government or security official has pointed the finger at anyone, the incidents come amid rising concern in Europe about state actors, chiefly Russia and Iran, orchestrating low-level sabotage operations. Last month, the head of Britain's domestic spy agency MI5, Sir Ken McCallum, warned that "Russia remains aggressor number one" and said Moscow was escalating its attempts at hybrid warfare while staying below the threshold that would trigger NATO's collective defense. Poland this week reported suspicious activity near its border with the Russian exclave of Kaliningrad, saying a fast security response may have prevented a "serious provocation," and a wave of cyberattacks has targeted European grocery chains' refrigeration systems and French blood banks.

McCallum also said Iran was using criminal proxies across Europe, pointing to a wave of arson and sabotage incidents targeting Jewish communities in the U.K. and other European nations. Many of those attacks were claimed by a group calling itself Harakat Ashab al-Yamin al-Islamiya, or HAYI, which U.K. authorities have sanctioned and say is tied directly to the Quds Force of Iran's Islamic Revolutionary Guard Corps.

Barry Andrews, an Irish member of the European Parliament, referred to the diverted Aer Lingus flight in a social media post, writing: "This after several hybrid threats and attacks across Europe, and ahead of the major European summit in #Dublin next week. Does anyone still deny Ireland faces serious security threats?"