Russia's Federal Security Service (FSB) said Friday a Russian national had been detained in Moscow on suspicion of treason and had confessed to assembling and launching drones on behalf of Ukraine.

In a statement, the FSB said that the man, whom it did not name, had "assembled and launched unmanned aerial vehicles to create false targets in the immediate vicinity of Russian Defense Ministry facilities."

The Interfax news agency cited a video released by the FSB as saying that the man had worked for the Freedom of Russia Legion, a group of armed pro-Ukrainian Russian exiles.

In recent months, Kyiv has stepped up strikes against economic targets inside Russia, hitting a string of oil refineries and metal plants.