Russia is suspected of a plot to attack cargo planes in Europe and the US

European security officials have linked suspected Russian agents to a plot to smuggle incendiary devices onto a cargo plane in Germany, which investigators say could be a test run for future attacks on planes bound for North America.

An international investigation that began after one of the devices caught fire prematurely in July found that the conspirators also sent packages without the flammable contents to U.S. and Canadian addresses, in an apparent test to see if the packages could be successfully delivered , according to the European security service. civil servants.

The plan to cause fires on board aircraft was seen as a provocative and particularly dangerous escalation in an alleged sabotage campaign led by Moscow against NATO countries helping Ukraine defend itself against a Russian military invasion. Russia has denied any link to such plots.

The new revelations come ten days after the Polish Public Prosecution Service announced the arrest of four people as part of an ongoing investigation. according to a statement in “activities of foreign intelligence services through acts of sabotage” in Poland and other European Union member states. Arrest warrants were issued for two other individuals who were still at large.

The suspects were accused of sending packages containing “disguised explosives and hazardous materials” via international courier services, prosecutors said.

“The group’s goal was also to test the transmission channel for such packages, which would eventually be sent to the United States of America and Canada,” the statement said.

Three European security officials confirmed that the packages were linked to a sabotage plot involving suspected Russian agents or their proxies. The officials, who spoke on condition of anonymity to discuss an active investigation, said it was unclear whether the plan was driven by the Kremlin or lower intelligence officials.

One of the European officials said the plot appeared to be in its early stages and relatively simple. New details of the investigation were first reported Monday by the Wall Street Journal.

German law enforcement officials were initially alerted to the plot when a fire broke out at a freight hub in Leipzig, Germany, operated by Germany-based international carrier DHL. The fire was traced to a package containing an electronic massage device that had been modified with the addition of a highly flammable form of magnesium.

The package came from Lithuania and caught fire during a stopover. According to a German security official, it was marked for delivery to a false address in Birmingham, England.

Fortunately, the package “ignited on the ground rather than during a flight, preventing a catastrophic situation,” the official said. “If it had exploded in mid-air it could have led to a crash, with the debris potentially injuring people on the ground.”

The same sender shipped packages to U.S. and Canadian addresses without the flammable contents, according to a second European official familiar with the investigation.

“These packages were considered test runs by the sender, who wanted to test how far they could reach,” the official said.

Biden administration officials have declined to discuss details of the alleged firebombing attempt. A senior US official said there are “currently no active threats regarding flights to the US.”

A spokesperson for the U.S. Transportation Security Administration said in a statement that the agency has implemented additional security measures to prevent tampering with cargo shipments to the U.S.

“We continually adapt our security posture as necessary and promptly share all relevant information with our industry partners to include requirements and recommendations that will help them reduce risk,” the spokesperson said.

Russian officials could not be reached for comment Monday. Kremlin spokesman Dmitry Peskov previously told The Washington Post that the accusations of Russian sabotage activities were “nothing more than fueling Russophobic hysteria.”

Greg Miller, Ellen Francis and Ian Duncan contributed to this report.