BERLIN — A series of suspicious events near military bases and critical infrastructure across Germany has sent policymakers and military officials into a panic.

This month, repeated nighttime drone flights were spotted over an area of ​​critical infrastructure in the far north of the country. The unmanned vehicles were apparently seen spying on a decommissioned nuclear power plant, a large chemical factory and a liquefied natural gas terminal, German public broadcasters reported.

The LNG plant was built in a hurry to help Germany wean itself off Russian gas after Putin’s large-scale invasion of Ukraine in February 2022.

The public prosecutor’s office is keeping quiet about the case, but the police in Schleswig-Holstein have asked the German army for support. The intruding drones fled at speeds of up to 100 kilometers per hour and were faster than the police drones, reported Der Spiegel. The German army has provided the public prosecutor’s office with radar data and other information, a spokesman for the Ministry of Defense told the German Press Agency.

The public prosecutor’s office in Flensburg, the capital of the northern federal state, has launched an investigation into the case on suspicion of espionage for the purposes of sabotage, the French news agency AFP reported.

Last week the NATO air base in Geilenkirchen, West Germany was temporarily the second highest alert level after foreign intelligence services suspected an imminent threat. German media reported that the danger allegedly came from drones, although German authorities have not publicly confirmed this.

A spokesman for the base told reporters last week that “nothing had flown over the base” and described speculation to the contrary as “absurd”.

Officials at the U.S. European Command, which oversees the U.S. troop presence in Germany and other parts of the continent, declined to discuss specific threats. The command “routinely implements and adjusts appropriate force protection measures to ensure the safety of our personnel and equipment,” a spokeswoman wrote in a statement for this article.

“As always, USEUCOM advises personnel in the European theater to remain vigilant, report suspicious activity, and take prudent steps to minimize risk. The safety and security of our military communities is our highest priority.”

Unidentified drones have been reported over military training grounds, including those where Germany trains Ukrainian soldiers. The flights and suspicious activities have been going on for over a year, but there seems to have been little progress in countermeasures or investigations into their origins.

However, German intelligence services suspect Russian involvement.

In April, two Germans of Russian descent were arrested in Bavaria for allegedly planning sabotage attacks for Moscow in Germany. Prosecutors claim that they had already scouted railway lines, military training areas and defense infrastructure for this purpose.

The Munich “Süddeutsche Zeitung” reported this week that more than 400 drone flights over or near German military restricted areas were reported in 2023 alone.

Meanwhile, the US Department of Defense expects to soon receive new technology for drone defense. Thomas Hitschler, the agency’s Parliamentary State Secretary, explained in a letter to parliamentarians at the beginning of the summer that the Bundeswehr would be supplied with the new system by the end of the year.

He made it clear that the defence against drones in and over military installations is the responsibility of the Bundeswehr, but outside military bases it is the responsibility of the state police.

Since the Russian invasion of Ukraine, investments in the German army have increased significantly. Chancellor Olaf Scholz spoke of a “turning point” in the war. His government strengthened defense budgets and began to address the long-standing deficits of the German armed forces.

Concerns about possible Russian sabotage have spread across Western Europe. Earlier this year, a key communications cable was severed at an air force base in the Nordic country in what Norwegian authorities described as a “deliberate action”. Cables from the Norwegian hydrophone system that Oslo uses to monitor movements in the North Sea were also severed.

Other, as yet unresolved, cases of apparent sabotage, such as cases of apparent arson in countries such as Poland, the United Kingdom and the Baltic states, suggest that a foreign actor harboring a grudge against the West may be increasing its unconventional warfare activities.

The German domestic intelligence service has repeatedly warned publicly about hybrid warfare, most recently in July: “The cases observed across Europe since 2023 and increasing indications of possible activities in Germany are currently leading to an adjusted assessment,” warned the Federal Office for the Protection of the Constitution. “There is an increased risk of sabotage activities or corresponding preparatory actions in Germany.”

The focus of its attention is on “hybrid threats such as cyberattacks and espionage, particularly by the Russian regime,” the secret service said in its latest annual report.

Noah Robertson in Washington contributed to this report.