Ukraine has staged a string of damaging attacks on Crimea in the course of the 22-month-old war, including on warships, airfields, the headquarters of Russia's Black Sea fleet and the bridge that connects the peninsula to southern Russia.
Russia's defence ministry said the Ukrainian guided missiles were shot down by its air defences. There was no immediate word from Ukraine.
Mikhail Razvozhayev, Russian-installed governor of the Crimean city of Sevastopol, said all services were on high alert and urged residents to remain calm.
Russia seized Crimea from Ukraine in 2014 and used it as one of the launchpads for its full-scale invasion of its neighbour in February 2022.
Ukraine, despite lacking any substantial navy of its own, has managed to inflict a series of blows on Russia's, most recently when it struck a large Russian warship with cruise missiles late last month in the Crimean port of Feodosia.
The New Year period saw an intensification of Russian missile and drone strikes on Ukraine. Ukraine hit back with attacks in southern Russia, where authorities said 25 people were killed in the Belgorod region last Saturday.
Regional governor Vyacheslav Gladkov said military experts were working to defuse three pieces of unexploded Ukrainian ordnance in the city of Belgorod on Thursday that forced authorities to evacuate 600 people from their homes.
Cross-border strikes into southern Russia have become a regular occurrence but Saturday's was by far the deadliest, overshadowing New Year celebrations and prompting some residents to leave in fear of further attacks.
Sources in the city told Reuters that some people were heading away by bus or car after finding that train tickets to Moscow had sold out, but the scale of the departures was not clear.
(Reporting by Reuters; Writing by Mark Trevelyan and Alexander Marrow, Editing by Timothy Heritage)
