意大利数百所学校因炸弹威胁疏散，欧洲多地接连受扰Hundreds of Schools in Italy Are Evacuated as More Bomb Threats Rattle Europe

Hundreds of Schools in Italy Are Evacuated as More Bomb Threats Rattle Europe No explosives were found, Italian officials said, after planes and news outlets in Europe were targeted with threats last week. The hoaxes have added to anxiety over hybrid attacks on the continent.

Hundreds of schools in Italy and elsewhere in Europe were evacuated on Wednesday after receiving emailed bomb threats that were determined to be hoaxes, officials said, adding to disruptions after flights and news outlets across the continent were targeted with similar threats last week.

The latest messages, which were also sent to schools in Ireland, Northern Ireland and Scotland, appeared to be part of a coordinated campaign to sow confusion across Europe, officials said, even as they indicated that they did not know who was behind them.

Italy’s education ministry said that some 6,300 schools had received the anonymous threats. Education Minister Giuseppe Valditara said that Italy’s intelligence agencies were investigating and suggested a link to other recent disruptions in Europe, including apparent cyberattacks on supermarket refrigeration systems and blood banks.

“It’s not the first time,” Mr. Valditara told “l’Aria che Tira,” a morning talk show on the La7 channel in Italy. “We obviously need to be vigilant, but we must also be aware that in a context where hybrid warfare is increasingly being used as a tool to destabilize nations and economies, we need to prepare ourselves.”

Prime Minister Giorgia Meloni of Italy called a meeting of ministers and cybersecurity officials on Wednesday but said that “at this time, the investigations conducted have not revealed any evidence to suggest that a concrete danger exists.”

“Rather,” she added in a statement on social media, “they appear to be part of a strategy aimed at causing alarm and concern.”The police in Scotland said that “threatening messages were sent to a number of schools” on Wednesday morning. “These messages were immediately assessed and are being treated as hoaxes,” the police said in a statement, adding that they were not advising schools to evacuate.

Similar emails sent to schools in Ireland and Northern Ireland were also being treated as a hoaxes, officials said. Northern Ireland’s Education Authority said in a statement, “We strongly condemn these malicious emails and the distress and disruption caused to school communities.”Officials have emphasized that the extent of the threats remains limited. The number of flights affected last week, for example, was a fraction of the tens of thousands that operate daily in Europe. But anxiety is running high on the continent, where hybrid warfare attacks and intimidation tactics have shaken air travel and other industries in recent months as Russia’s war against Ukraine spills over its borders. What happened last week?

Bomb threats targeted several European airlines, disrupting dozens of flights and forcing emergency landings, some accompanied by military jets. No explosives were found on any of the flights, according to officials.

On Friday, Czech police said that Prague’s main airport had received threats of explosives placed aboard arriving and departing flights. The Hungarian defense minister, Romulusz Ruszin-Szendi, said that Hungarian fighter jets had temporarily escorted one of the flights.

Officials at Copenhagen’s airport also said that Danish police had responded to threats to flights, without giving details.

A day earlier, officials said that targeted flights included an Aer Lingus plane flying to Rome from Dublin that was diverted to an air base in France; four planes heading to Prague; two LOT Polish Airlines flights, bound for Paris and Brussels; and two Aegean Airlines flights, from Thessaloniki to Milan and from Athens to Vienna. A series of similar threats on Nov. 3 disrupted flights in Poland, Spain, Bulgaria and Italy.

Nerves were further rattled on Friday after the offices of several news media outlets in Ireland and other European countries were evacuated following bomb threats that turned out to be hoaxes. Nova, a Bulgarian news media organization, reported that it had received a bomb threat by email that also claimed responsibility for the threats against planes. What are officials saying?

On Friday, after the threats to media companies, the Irish government said in a statement: “It seems likely that this is a coordinated campaign of disruption.”Heidi Alexander, Britain’s transport secretary, told British news media last Thursday that the government was taking the “malicious hoax threats” seriously, but that they were not believed to be credible.

Officials at Aeroporti di Roma, which manages Rome’s two commercial airports, said that one threat arrived Thursday morning in an email written in Italian with the subject line “threat notification.”A spokesman for the airport operator said that the email had been sent from “fighters of the male state” who said they wanted to “turn the skies red” with explosions.

Police Scotland noted that the messages on Wednesday were “sent widely to distribution lists across the U.K. and Northern Ireland and our assessment remains that they do not represent a credible threat.”The agency’s Cyber and Fraud Unit was investigating, it said. What else has Europe on edge?

A number of European countries have been affected by suspected cyberattacks on supermarket refrigeration systems, including France in October and Ireland, Sweden, Belgium and Luxembourg this month.

On Monday, French officials accused Iran of orchestrating the October attack and issued international arrest warrants for three Iranians “affiliated with the Electronic and Cyber Center of the Islamic Revolutionary Guards Corps.”And on Nov. 4 France said that a cyberattack had targeted blood banks by raising the temperatures in storage refrigerators. It is not clear whether the cyberattacks are linked to the bomb threats. What is the goal?

Neither the identities of those making the threats nor their motives are clear. But some officials and experts have sought to find a logic behind the targets. For example, Ireland — where media companies and the national air carrier, Aer Lingus, received threats — is hosting summits of European and global leaders this week.

Peter Neumann, a professor of security studies at King’s College London, said he saw hallmarks of a hybrid attack: The targets were diffuse, and the goal seemed to be disruption. “The aim of a hybrid campaign is to create chaos, uncertainty and a sense of threat,” he said.

But analysts agreed that it can be extremely difficult to attribute these kind of threats to any one actor or group with confidence. The Irish government’s statement said it was unclear whether the threats were from “individuals or a centralized or coordinated effort.”“Bomb threats are incredibly cheap, and they are low-risk in the sense that they’re pretty easy to obscure,” said Rhys Jones, a security analyst at Osprey, an aviation risk consultancy, meaning a variety of people are capable of performing them, including teenagers or pranksters. Why are the hoaxes so disruptive?

Marco Chan, a lecturer in aviation operations at Kingston University in London, said that even if a bomb threat is assessed as a probable hoax, it is difficult for the authorities to determine that for certain without carrying out a thorough search.

As a result, he said, if a threat is received while a flight is in the air, the authorities have little choice but to ground the aircraft for emergency inspections.

“If there is a shred of concern as to whether there is a bomb threat, they should always treat it as genuine,” Mr. Chan said.

An earlier version of this article misstated where an Aer Lingus flight to Rome had originated. It was Dublin, not Dubai.

We acknowledge mistakes in our reporting with corrections. If you spot an error, please let us know at corrections@nytimes.com. Learn more.

Jonathan Wolfe is a Times reporter based in London, covering breaking news.

Elisabetta Povoledo is a Times reporter based in Rome, covering Italy, the Vatican and the culture of the region. She has been a journalist for 35 years.

Ali Watkins covers international news for The Times and is based in Belfast.