When Prime Minister Donald Tusk of Poland accused Russian agents last month of planting explosives on a rail line, he

called it “perhaps the most dangerous situation for the security of the Polish state” in years, even though no one was

hurt.

Around the same time, Defense Minister Guido Crosetto of Italy urged Europe to protect itself better from disinformation

that he said Russia directed at his country. “We are under attack, and the hybrid bombs keep falling,” he concluded in a

report.

The European Union’s top diplomat, Kaja Kallas, was even more blunt. “Russia is committing state-sponsored terrorism,”

she said recently.

Hybrid attacks against Europe — a barrage of drone incursions, cyberstrikes and acts of sabotage that stop short of open

warfare — are on the rise from a relative lull earlier this year, according to military officials and experts who have

long believed that Russia is to blame for the assaults and is using them to test NATO allies. In the past few months

alone, the hybrid assaults included jamming aviation-navigation systems over Sweden, sending drones over Danish and

Belgian airports and smuggling explosives into Poland in cans of corn, officials have said.

In response, European countries are changing their tone. Officials are rebuking Russia more forcefully and more often,

embracing a naming-and-shaming strategy that just a year ago divided the North Atlantic Treaty Organization.

There are risks. President Vladimir V. Putin of Russia warned Europe on Tuesday about appearing more assertive. “We are

not planning to fight with Europe, but if Europe suddenly starts a war with us, we are ready right now,” Mr. Putin said.

Thank you for your patience while we verify access. If you are in Reader mode please exit and log into your Times

account, or subscribe for all of The Times.

Thank you for your patience while we verify access.

Already a subscriber? Log in.

Want all of The Times? Subscribe.