"During the investigation of the sabotage planned in May 2023 to blow up long-range aircraft stationed at the Severny airfield in the Ivanovo region, it became known about the plans of the Main Intelligence Directorate of the Ukrainian Defense Ministry to commit a terrorist act in Russia using the so-called 'dirty bomb,'" the FSB said in a statement.
Ukraine planned to deliver and plant "dirty bombs" equipped with delay timers to simultaneously blow up and render the area uninhabitable, the statement read.
Additionally, the FSB released a video of the interrogation of two detained Ukrainian pilots. They confessed that Kiev considered transferring small portable nuclear charges to Russia to carry out terrorist attacks.
"Earlier, the leadership of Ukrainian intelligence discussed the possibility of creating and transferring [to Russia] a 'dirty' nuclear bomb for radioactive contamination, small portable nuclear charges. They don't weigh that much," one of the pilots said.
The second pilot said that he had been given the task to conduct bombing in Russia’s western Bryansk Region. He specified that the target was a fuels and lubricants depot.
Ukraine’s special services have been engaged in attacks on Russian civilian infrastructure, targeting the energy grid. The Kiev regime has been firing rockets at the Zaporozhye Nuclear Power Plant, the largest facility of its kind in Europe, creating considerable risks that could lead to a nuclear disaster.