Russia’s Black Sea Fleet headquarters in the port city of Sevastopol in Crimea was hit by a Ukrainian missile, local authorities reported Friday.

The headquarters building was damaged, and one serviceman was missing, Russia’s Defense Ministry said in a Telegram statement. Air defenses shot down five missiles, it said.

A fire in the building was being dealt with by emergency services, Sevastopol’s Moscow-appointed Governor Mikhail Razvozhayev wrote in a social-media post. Debris is scattered over a wide area, Russia’s state-run Tass news service reported.

Crimea, which Russia annexed from Ukraine in 2014, has come under repeated attack by drones or missiles in recent months as Ukrainian forces press their counteroffensive aimed at retaking occupied territory in the country’s south and east. A navy ship and submarine were destroyed in dry dock at a shipyard in Sevastopol last week, and the bridge linking Russia to the peninsula was partially damaged in an attack in July.

Russia’s fleet in Crimea has two options, “voluntary or forced self-liquidation,” Ukraine’s National Security and Defense Council Secretary Oleksiy Danilov said Friday on social media. He threatened that the fleet “will be sliced up like salami” as Ukrainian forces conduct high-precision strikes on military infrastructure targets.

Russian officials in Crimea said local internet services were also under “unprecedented cyberattack” causing outages in the peninsula, Tass reported.

(Updates with Russian Defense Ministry in second paragraph, Ukrainian comment in fifth)