KYIV, Ukraine — Ukraine struck the headquarters of Russia’s Black Sea Fleet in a missile attack Friday that left a serviceman missing and the main building smoldering, according to military officials on both sides of the war and images from the scene in Crimea.

The Russian Defense Ministry initially said one servicemember was killed but then issued a subsequent statement saying he was missing following the attack in the port city of Sevastopol.

The Crimean Peninsula, which Russia illegally annexed from Ukraine in 2014, has been a frequent target since Russian President Vladimir Putin ordered a full-scale invasion of Ukraine almost 19 months ago.

Crimea has served as the key hub supporting Moscow’s invasion of Ukraine. Sevastopol, the main base of Russia’s Black Sea Fleet since the 19th century, has had a particular importance for navy operations since the start of the invasion of Ukraine.

Ukraine has increasingly targeted naval facilities in Crimea in recent weeks while the brunt of its summer counteroffensive makes slow gains in the east and south of Ukraine, the Institute for the Study of War said Thursday in its daily assessment of the conflict. Military experts say it is essential for Ukraine to keep up its long-range attacks on Russian military assets in Crimea to degrade morale and weaken its enemy.

Previous attacks resulted in several civilian deaths, but Russian officials haven’t yet reported any military personnel killed. Six people were reported wounded following a July 2022 attack on the fleet’s headquarters, but it wasn’t clear whether they were civilians or servicemembers.

The Russian-installed governor of Sevastopol, Mikhail Razvozhayev, said no one was injured Friday outside of the burning headquarters building, but he didn’t provide information on other casualties. Firefighters battled the blaze, and more emergency forces were being brought in, an indication the fire could be massive.

Ukraine Claims Success

The Ukrainian military claimed responsibility for the attack, which it claimed was a success.

“We promised that ‘there will be more,’” Lt. Gen. Mykola Oleschuk, the air force commander, said in a social media post that thanked pilots and showed video of air sirens blazing and smoke rising from the building.

The Russian Defense Ministry said five missiles were shot down by Russian air defense systems responding to the attack on Sevastopol. It was not immediately clear if the headquarters was hit in a direct strike or by debris from an intercepted missile.

Sevastopol residents said they heard explosions and saw smoke, Russian news outlets reported, and images showed gray plumes over the seafront. The Associated Press could not immediately verify the videos.

A stream of ambulances arrived at the fleet’s headquarters, and shrapnel was scattered hundreds of meters (yards) around, Russian state news agency Tass reported.

Oleg Kryuchkov, an official with the Crimean administration, said one cruise missile downed near Bakhchysarai, about 18.5 miles inland, sparked a grass fire.

Razvozhayev said civilian infrastructure wasn’t damaged but did not mention the impact on the fleet headquarters.

He initially warned Sevastopol residents that another attack was possible and urged them not to leave buildings or go to the city center. He later said there was no longer any threat of an air strike but reiterated calls not to go to the central part of the city, saying roads were closed and and unspecified “special efforts” were underway.

Police asked residents to leave the central part of the city, Tass said.

The reported attack came a day after Russian missiles and artillery pounded cities across Ukraine, killing at least five people as President Volodymyr Zelenskyy met with U.S. President Joe Biden and congressional leaders in Washington with an additional $24 billion aid package under consideration.

The attack Friday is one of several launched by Ukraine recently in the Crimea area.

The Institute for the Study of War said satellite imagery this week showed that Ukrainian strikes had significantly damaged a communications command center in Verkhnosadove, just outside Sevastopol.

Russian-installed authorities in Sevastopol accused Ukraine on Sept. 13 of carrying out the biggest attack in Crimea in weeks, one on a strategic shipyard that damaged two ships undergoing repairs and caused a fire at the facility.

Two days earlier, Ukraine claimed it had recaptured strategic gas and oil drilling platforms in the Black Sea that Russia seized in 2015. Russia had used the platforms for electronic warfare equipment and to launch helicopters, and Ukraine said getting control of them would help it regain Crimea.

In other war developments, ongoing shelling in southern Ukraine’s Kherson region killed one man and injured another, according to regional Gov. Oleksandr Prokudin.

“Kherson has been restless since the morning,” he said on Telegram.

Russian shelling sparked fires in a residential building and a garage.

In Kharkiv, regional Gov. Oleh Synyehubov said over 14 settlements came under attack. A house was damaged and a fire broke out in Vovchansk, in Chuguyiv district. There were no casualties, the governor said.