"As a result of the measures taken in Moscow, a Russian citizen, who planned to organise a terrorist act in July by detonating an improvised explosive device in crowded places, was arrested", the statement says.
The components of an IED were found in the cache equipped by him, and instructions for its manufacture and correspondence with members of international terrorist organisations located in Syria were found in the communications equipment used.
The investigation department of the FSB has opened a criminal case, operational search activities and investigative actions are continuing.
"The identity of the terrorist has not been disclosed in the interests of the investigation", the FSB noted.