German authorities on Tuesday detained two men accused of attempting to disable German Navy vessels, amid a broader wave of suspected sabotage incidents across Europe since Russia’s full-scale invasion of Ukraine.

The Hamburg public prosecutor’s office said in a statement that a 37-year-old Romanian national and a 54-year-old Greek national had been arrested in Hamburg and a village in northern Greece, respectively. Authorities also searched three properties in Hamburg, Greece and Romania.

Prosecutors said the suspects worked at the Port of Hamburg and had carried out acts of sabotage on several corvettes — the smallest class of warship — intended for the German Navy. The damage included pouring some 20 kilograms of grit into an engine, puncturing water lines, removing fuel caps and disabling safety switches.

The Hamburg authorities said they were looking into who else might be behind the attacks.

German lawmaker Roderich Kiesewetter, from the ruling coalition Christian Democrats, told POLITICO on Tuesday: “The modus operandi and the apparent objective fit a Russian pattern of using targeted acts of sabotage against militarily relevant and critical infrastructure to prepare for attacks and spread terror in Germany through hybrid methods.”

However, he added: “It is necessary to wait and see whether this assessment applies in this case as well.”

Europe has suffered at least 145 sabotage incidents since the beginning of Russia’s full-scale invasion of Ukraine in 2022, according to a study by the AP news agency. The acts, which have tended not to cause fatalities or significant damage, have disrupted Europe by keeping intelligence, police and prosecution assets busy with cross-border investigations. AP reported that Russia has in some cases used common criminals to perform minor acts of sabotage.

In Greece, authorities said the arrest warrant for the Greek national had been issued on Oct. 10 for acts of sabotage against defense equipment. EU justice agency Eurojust said that if the acts had gone undetected, they “would have caused major damage to the ships and delayed their departure, endangering the operations of the German Navy.”

Germany has been Ukraine’s biggest EU donor since Russia invaded in February 2022. In May 2024 an arson attack targeted an arms manufacturer in Berlin; the Wall Street Journal later reported that individuals linked to Russian sabotage efforts were behind the fire.

In November 2024 a DHL cargo plane departing from Leipzig crashed into a building in Lithuania’s capital, Vilnius, after a parcel exploded, killing the plane’s captain. Lithuanian authorities later said it had been organized by Russians with intelligence ties.