The Russian Navy's guided missile cruiser Moskva sails back into a harbour after tracking NATO warships in the Black Sea, in the port of Sevastopol, Crimea November 16, 2021.
The Russian Navy's guided missile cruiser Moskva sails back into a harbour after tracking NATO warships in the Black Sea, in the port of Sevastopol, Crimea November 16, 2021. Reuters / Alexey Pavlishak

Russia said the crew of its Moskva warship were evacuated on Thursday after an explosion of ammunition aboard that Ukraine said was caused by a missile strike, and a U.S. defence official said the stricken vessel was still trying to put out a fire.

The warship, Russia's Black Sea fleet flagship, is still believed to be afloat and the United States is under the assumption that it is heading to Sevastopol, the senior U.S. official said.

"Our assessment is that she still appears to be battling a fire on board," the official added.

Russia's defence ministry said the fire on the Soviet-era missile cruiser had been contained but left the ship badly damaged. It did not acknowledge the ship, which had more than 500 sailors aboard, had been attacked and said the cause of the fire was under investigation.

Ukraine's southern military command said it hit the warship with a Ukrainian-made Neptune anti-ship missile and that it had started to sink.

Reuters was unable to verify any of the various statements.

The United States said it did not have enough information to determine whether the ship was hit by a missile.

"We don't have the capacity at this point to independently verify that but certainly, the way this unfolded, it's a big blow to Russia," said national security adviser Jake Sullivan.

The Moskva's loss or disabling would be a fresh hit to Russia's stuttering campaign on the 50th day of the war as it readies for a new assault in the eastern Donbas region that is likely to define the conflict's outcome.

Commenting on Russia's setbacks, CIA Director William Burns said the threat of Russia potentially using tactical or low-yield nuclear weapons in Ukraine cannot be taken lightly, but the CIA has not seen a lot of practical evidence reinforcing that concern.

Russian forces have pulled back from some northern parts of Ukraine after suffering heavy losses and failing to take the capital Kyiv. Ukraine and its Western allies say Moscow is redeploying for a new offensive.

"Russian forces are increasing their activities on the southern and eastern fronts, attempting to avenge their defeats," Ukrainian President Volodymyr Zelenskiy said in a Wednesday night video address.

Russian aviation destroyed seven military facilities in Ukraine in the past 24 hours, including an artillery missile depot, Interfax quoted the Russian defence ministry as saying.

Russia's navy has fired cruise missiles into Ukraine and its Black Sea activities are crucial to supporting land operations in the south of the country, where it is battling to seize full control of the port of Mariupol after weeks of bombardment.

Russian media said the Moskva was armed with 16 anti-ship cruise missiles with a range of at least 700 km (440 miles). Kyiv says the Moskva featured in one of the landmark early exchanges of the war, when Ukrainian border guards on Snake Island in the Black Sea told the ship to "Go fuck yourself" after it demanded they surrender.

'MASSING TROOPS'

Ukrainian Deputy Defence Minister Hanna Malyar said Russia was massing troops not only along the Russia-Ukraine border, but also in Belarus and Moldova's breakaway Transdniestria region. Moldova separately accused Russia's army of trying to recruit Moldovans. Moscow's foreign ministry did not immediately respond to a request for comment.

Authorities in Transdniestria, bordering southern Ukraine, denied Russia was preparing forces there to threaten Ukraine.

The Kharkiv, Donetsk and Zaporizhzhia regions in the country's east were being hit by missile strikes, Malyar said.

Kharkiv's governor said shelling killed four civilians.

Russian officials said Ukrainian helicopters had hit residential buildings and injured seven people in the Bryansk region, the latest of a series of cross-border attacks that Moscow has said may trigger a retaliatory attack on Kyiv.

The governor of the Belgorod region said a village there was also attacked, but that no one was wounded. Neither side's statements could be independently verified and Ukraine's military did not respond to requests for comment.

Russia said on Wednesday more than 1,000 Ukrainian marines from one of the units still holding out in the shattered city of Mariupol had surrendered. Ukrainian officials did not comment.

If taken, it would be the first major city to fall to Russian forces since they invaded, allowing Russia to reinforce a land corridor between separatist-held eastern areas and the Crimea region it seized and annexed in 2014.

'FORGIVE US'

Ukraine says tens of thousands of people are believed to have been killed in the city.

Mariupol's mayor, Vadym Boichenko, said Russia had brought in mobile crematoria "to get rid of evidence of war crimes" - a statement that it was not possible to verify independently.

Moscow has blamed Ukraine for civilian deaths and accused Kyiv of denigrating Russian armed forces.

In the village of Lubianka northwest of Kyiv, from where Russian forces had tried and failed to subdue the capital before retreating, a message to Ukrainians had been written on the wall of a house that had been occupied by Russian troops.

"We did not want this ... forgive us," it said.

The Kremlin says its "special military operation" seeks to demilitarise and "liberate" Ukraine from nationalist extremists, a message villagers said was repeated to them by Russian troops.

"To liberate us from what? We're peaceful ... We're Ukrainians," Lubianka resident Viktor Shaposhnikov said.

Andriy Nyebytov, head of the Kyiv region police, said more than 800 bodies had been found in three districts which had been occupied by Russian forces.

"We are finding terrible things: buried and hidden bodies of people who were tortured and shot, and who died as a result of mortar and artillery fire," Nyebytov said in televised comments. His statements could not immediately be verified.

Russia has denied attacking civilians and said some reports have been staged for propaganda purposes.

RUSSIA ISOLATED

Warning that spillover effects from the Ukraine war were worsening crises elsewhere, U.N. aid chief Martin Griffiths released $100 million in emergency funding for Somalia, Ethiopia, Kenya, Sudan, South Sudan, Nigeria and Yemen.

The IMF will cut its global growth estimates for 2022 and 2023 as the conflict drives food and energy prices higher, piling pressure on already fragile economies, Managing Director Kristalina Georgieva said, warning the world was in "a very dangerous time".

Moscow's incursion, the biggest attack on a European state since 1945, has seen more than 4.6 million people flee abroad, killed or wounded thousands and raised fears of conflict between Russia and the United States, the world's top nuclear powers.

Western-led sanctions have triggered the worst economic crisis in Russia since the 1991 fall of the Soviet Union, say analysts.

The conflict has also galvanised NATO and prompted Russia's neighbours Sweden and Finland to discuss joining the Western military alliance.

Dmitry Medvedev, deputy chairman of Russia's Security Council and a close ally of President Vladimir Putin, warned that such a move would force Russia to boost its defences in the Baltic region, including with nuclear weapons.