The governor of Russia's Voronezh region, Alexander Gusev, warned citizens on Monday of a possible unmanned aerial vehicle (UAV) attack.

"Attention! Dear residents of the Voronezh region, the danger of a UAV attack has been declared on the territory of the region. Please remain calm. Air defense forces are at the ready. Follow further alerts from the regional government or from the Ministry of Emergency Situations of Russia," Gusev wrote on Telegram.