Russia's Black Sea Fleet repelled a drone attack on the Crimean port of Sevastopol in the early hours of Monday, the Moscow-installed governor of the city said through social media.
"According to the latest information: one surface drone was destroyed ... the second one exploded on its own," governor Mikhail Razvozhaev wrote on the Telegram messaging app. "Now the city is quiet."
No damage was reported, Razvozhaev added.
Sevastopol, along with the rest of the Crimean peninsula, was declared annexed by Russia in 2014 but is internationally recognized as part of Ukraine.
There was no immediate reaction from Ukraine. Kyiv almost never publicly claims responsibility for attacks inside Russia and on Russian-controlled territory in Ukraine.