Ukraine carried out a fiery missile strike on Friday on the main headquarters of Russia’s Black Sea Fleet, a Russian official said. Videos and photos showed large plumes of smoke over the building in Sevastopol in annexed Crimea.

The Russian-installed governor of Sevastopol, Mikhail Razvozhayev, said there was no information about casualties.

He said firefighters were battling a blaze, and more emergency forces were being brought in, an indication that the fire could be massive.

A stream of ambulances were arriving at the fleet’s headquarters and shrapnel was scattered hundreds of metres around, the Tass news agency reported. Razvozhayev initially warned Sevastopol residents that another attack was possible and urged them not to leave buildings or go to the city centre.

He later said there was no longer any air strike danger but reiterated calls not to go to the central part of the city, saying roads were closed and unspecified “special efforts” were underway.

Ukrainian officials, who have claimed responsibility for a series of other recent attacks on Crimea, didn’t immediately announce Kyiv launched the strike.

Sevastopol residents said they heard explosions in the skies and saw smoke, Russian news outlets reported.

Images circulated in Ukrainian Telegram channels showed clouds of smoke over the seafront. The Associated Press could not immediately verify the videos.