Ukraine's armed forces carried out drone and missile strikes on Russia's Black Sea coast overnight, DPA reported, citing local authorities, BTA reported.
Sochi Mayor Andrey Proshunin said a Ukrainian missile attack had been repelled. Residents of the resort city reported sirens and explosions on social media.
Proshunin urged people to avoid the coast and coastal areas and seek refuge. According to media reports, flights at Sochi International Airport have been temporarily suspended. There are no reports of damage so far.
The Russian Defense Ministry announced that 32 Ukrainian drones were intercepted over the Ukrainian peninsula of Crimea, which was illegally annexed by Moscow in 2014. Local authorities reported damage to the power grid and power outages.
According to unverified reports and videos on social media, a large oil facility in Simferopol was hit overnight.
Kiev has previously struck fuel depots and refineries as part of its defensive campaign against the Russian invasion that began more than three and a half years ago, DPA notes.
Moscow-appointed head of the Republic of Crimea, Sergei Aksyonov, was quoted by TASS as confirming the information about damaged substations and adding that repair work was underway.