"Naval forces together with air defense forces are now repelling the attack of enemy's drones in the outer harbor. One drone has already been shot down. All [emergency] services are in readiness," Razvozhayev wrote on Telegram.
The governor also urged people to stay calm.
Later in the day, Razvozhayev said that a total of two drones had attacked Crimea and Sevastopol, but air defense successfully repulsed the attack.
"While trying to approach the Sevastopol harbor, a drone was shot down by air defense forces. The second drone, which some media reported about, has been shot down over the territory of the republic of Crimea," the Sevastopol governor said.
The situation is under control, with relevant services and forces ready for any development, according to Razvozhayev.