Bomb threats disrupt several flights across Europe

At least a dozen commercial flights made either unscheduled or high-alert landings in Austria, France, Italy, Belgium, Czechia, Spain, Serbia and Bulgaria, according to authorities in the various countries.

Planes made unscheduled landings in Evreux, France; in Vienna, Austria; and in Bulgaria. A flight from Finland landed in Rome as scheduled but with a military escort, and various others touched down at their scheduled destinations across the continent but amid security alerts.

The incident in France became public knowledge first, but the other similar reports soon followed.

No initial signs of a genuine threat, EU says still 'too early' to say if cases linked

This comes after a series of bomb threats leveled against several European flights earlier this week, prompting similar unscheduled landings.

Tuesday's incidents turned out to be hoaxes, and preliminary information shows no sign of dangerous materials reported in Thursday's threats as yet.

The European Union Commissioner for Transport and Tourism, Apostolos Tzitzikostas, wrote online that any threats against civilians were unacceptable.

"It is too early to draw conclusions on whether the reported incidents are linked," Tzitzikostas said. "National investigations remain ongoing."

What happened in the subsequent alerts across Europe?

News of a series of diversions and bomb scares trickled out during the course of the day, particularly late in the morning:

Finland's Finnair carrier reported that two planes landed at their scheduled destinations but amid security scares.

One Finnair flight from Helsinki to Rome landed with a military escort. Another plane from the Finnish capital, operated by Jettime, also landed in Vienna as scheduled.

A Wizz Air flight from Milan to Warsaw made an unscheduled landing in Vienna.

Bulgaria reported three aircraft making emergency landings because of bomb threats.

Three Ryanair flights to Sofia — from Copenhagen, Madrid and London Stansted — also all landed under high alert.

Two of them touched down in Sofia as scheduled and one diverted to Plovdiv, the airport's CEO said.

Italian news outlets and the Reuters news agency reported, citing airport sources, that two planes — an Aegean Airlines flight from Thessaloniki and a Ryanair flight from Porto — landed at the Malpensa airport in Milan as scheduled after receiving bomb alerts on Thursday morning.

Police in Madrid said that three flights at the Spanish capital's airport were affected by what they called hoax threats, saying that security forces searched the area and ruled out any risk.

Police in the Czech Republic later said that they were preparing officials at Prague airport for four landings after threats of improvised explosive devices being on board.

"We assess the relevance of the threats as low," Czech police said. "Nevertheless, we do not underestimate the threat, which is why all necessary security measures have been activated with the least possible impact on passengers and airport operations."

On Thursday afternoon, Air Serbia issued a statement saying a flight from Belgrade to Bucharest landed safely at its destination after receiving a bomb threat.

What do we know about the first incident outside Paris?

An Airbus A320 plane has been diverted to the Evreux airbase to the west of Paris following a bomb threat.

The office of French Prime Minister Sebastien Lecornu announced the incident on Thursday, saying it was monitoring the situation "in real time."

The flight was headed from Dublin, Ireland, to the Italian capital of Rome.

Tracking websites showed the plane, part of the Aer Lingus fleet, sharply deviating its course as it was around Paris' airspace and heading towards the more isolated airfield in Evreux.

France's air force said that it dispatched planes "as soon as the incident was reported."

"The aircraft has been diverted and is being escorted to Evreux airfield," it said.

Lecornu's office subsequently confirmed that the plane, part of the Aer Lingus fleet, had landed safely at the airfield.

What happened during the earlier disruptions?

The prior threats to commercial flights this week turned out to be hoaxes that nevertheless caused diversions and major security mobilizations.

In one case, the Italian air force escorted a plane to its emergency landing.

The threats targeted airlines including Poland's LOT, Scandinavian Airlines, Wizz Air and Ryanair.

While it's not yet clear if there is a link, these disruptions to commercial aviation also coincided with a series of apparent cyberattacks targeting freezer units in major supermarkets and even French bloodbanks.

All the cases remain nascent, but have the potential hallmarks of so-called hybrid attacks designed to cause maximum disruption with minimal effort and resources.