Polish security services broke up a Russian spy network and detained six people it says were preparing acts of sabotage and monitoring rail routes to Ukraine, according to Interior Minister Mariusz Kamiński and Defence Minister Mariusz Błaszczak.

The individuals were arrested on suspicion of having installed secret cameras to film transport infrastructure used to deliver aid to Ukraine, said Kamiński.

“It was a spy group collecting information for the benefit of those who attacked Ukraine,” Błaszczak told Polish Radio. “The entire spy network had been dismantled,” he added.

Internal Security Agency officers secured cameras, electronic equipment, as well as GPS transmitters that were to be mounted on transports with help for Ukraine, according to Kamiński.

He added that the group had also been ordered to carry out propaganda activities to destabilise relations between Poland and Ukraine and fuel negative emotions towards NATO.

There is also evidence the group had been paid by the Russian secret service. “For its intelligence activity, members of the group received regular payments,” Kamiński said in a statement.

Some of the cameras installed by the spy group were found close to Rzeszow-Jasionka airport, which had been converted into an international logistics hub delivering military and humanitarian aid to Ukraine. The small airport is used by military and cargo aircraft from the US and across Europe to deliver supplies that are further transported by trucks to the Ukrainian border.

The ministers’ announcement confirmed previous reports from RMF FM radio that pointed to six people with an Eastern background being arrested under suspicion of collecting information on behalf of the Russian secret service.

On Wednesday, Polish President Andrzej Duda met with CIA Director William Burns to discuss the security situation in Poland, according to the president’s office.

Several European countries have expelled Russian diplomats for alleged spying since the war in Ukraine broke out. Earlier this year, a Russian citizen was charged with spying for Russia in Poland between 2015 and April 2022.