Production was temporarily suspended at an electronics company in Russia's Volga river region of Chuvashia, some 1,300 km (800 miles) from the border with Ukraine, after two drones fell on the plant's territory, the head of the region has said.
The strike - among the deepest into Russia by a Ukrainian drone in more than three years of the war - caused no casualties, Chuvashia Governor Oleg Nikolayev said in a statement on the Telegram messaging app on Monday.
But "the responsible decision was made to temporarily suspend production to ensure the safety of employees" of the VNIIR enterprise where the drones fell, Nikolayev said.
It was not immediately clear whether the drones caused any damage. Nikolayev said that another drone fell onto some fields in the area of the capital of the region, Cheboksary.
Moscow's war efforts
The Russian defence ministry - which reports only how many drones were destroyed not how many Ukraine launched - said on Telegram that its units downed two drones over Chuvashia. In total, it said, air defence systems destroyed 49 Ukrainian drones overnight over Russia.
According to photos and videos on unofficial Russian and Telegram news channels, the drones sparked a fire at the VNIIR plant that they said produces components for electronic warfare.
Ukraine’s military has confirmed the attack, saying it targeted an electronics plant in Russia’s Chuvashia region.
Kiev has often said that its attacks inside Russia are aimed at destroying infrastructure key to Moscow's war efforts and are in response to the continued Russian strikes on Ukraine.
The VNIIR Russian Scientific Research Design and Technological Institute of Relay Engineering with experimental production in Chuvashia is on the US sanctions list, according to the US Treasury website.
A Ukrainian drone attack on the Voronezh region that borders Ukraine damaged a gas pipeline, cutting off gas supplies to 22 clients, the region's governor, Alexander Gusev, said on the Telegram instant messaging platform.
