This was announced by the National Guard, Censor.NET reports.
The man who was included in the database as an "LPR" militant was detained when he tried to cross the checkpoint at Horodyshche, the Luhansk region, in a VAZ vehicle.
The same unit of servicemen also detained a Russian citizen who was crossing the checkpoint in a Volkswagen car as a passenger.
The detainees have been transferred to the military counterintelligence service.
Related materials: Anti-Terrorist Operation