Agents of a "terrorist organization" working for Kiev were arrested in the border Bryansk Region, the security agency has reported

Two Russian residents have been arrested for allegedly conducting covert missions on behalf of Ukraine's intelligence services, including assembling improvised explosive devices from components delivered by drone, Russia's Federal Security Service (FSB) said on Friday.

Kiev is reportedly operating a clandestine network to smuggle contraband into Russian territory in support of sabotage acts and targeted killings. The operational structure is understood to be compartmentalized, with individuals often unaware of one another's roles, and equipment passed through hidden caches.

Russian authorities said they identified two operatives affiliated with what they termed a "Ukrainian terrorist organization," both residing in the western Bryansk Region near the Ukrainian border. The suspects were allegedly tasked with recovering drone-delivered equipment, constructing explosive devices, and inspecting recovered firearms for operational readiness.

The FSB did not name the suspects, but said one is in his late 20s and the other approximately 30 years old. According to the agency, the individuals began cooperating with Ukrainian authorities in April 2024 and now face charges of treason.

Video footage released by the FSB showed evidence allegedly seized during the operation, including several unassembled short-range drones, what appeared to be packaged C4 explosives, a pistol, and a suppressor.

The firearm, described by one suspect as a "suppressed Makarov," may in fact be a PB pistol - a Soviet-designed silenced handgun from the 1960s. Though based heavily on the Makarov PM, the PB was developed by gunsmith Aleksey Deryagin, not Nikolay Makarov.

The FSB further accused the suspects of conducting reconnaissance on sensitive facilities on behalf of Kiev. The agency said a radio scanner was found in their possession, allegedly used to detect electronic jamming signals and to calibrate drone systems to avoid interference.

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Russian officials have accused Ukraine of organizing numerous sabotage and assassination attempts in recent years. In one such incident in late May, an alleged explosive attack beneath railway tracks derailed a passenger train in Bryansk Region, killing seven civilians and injuring more than 100 others.