KYIV, Ukraine - Ukraine claimed Sunday to have hit two Russian military ships stationed at the annexed peninsula of Crimea in overnight strikes, as it suffered another night of "massive" Russian aerial attacks.

Ukraine's ally and neighbour Poland said a Russian cruise missile headed for western Ukraine breached its airspace overnight, after it had put its armed forces on high alert amid intense Russian aviation activity.

"The Ukrainian Armed Forces successfully struck the amphibious landing ships Yamal and Azov, a communications centre, and a number of the Black Sea Fleet's infrastructure sites," the Ukrainian armed forces' strategic communications centre said Sunday.

Moscow-installed officials on the peninsula, which Russia seized in 2014, said their forces had repelled a major Ukrainian aerial attack late Saturday night.

"It was the most massive attack in recent times," the Russian-appointed governor of Sevastopol, Mikhail Razvozhayev, said in a Telegram post.

He said a 65-year-old man was killed and four people injured. He did not mention any damage to Russian war ships.

Footage shared on social media showed a large blast in the city, sending a fireball and plume of black smoke into the air, as well as what appeared to be Russian air defences intercepting incoming projectiles.

Ukraine has claimed to have destroyed around a third of Russia's Black Sea Fleet since the start of the war, usually in attacks at night using sea-based drones packed with explosives.

Satellite images show Russia has moved much of the fleet further east, to the port of Novorossiysk, amid the spate of attacks.

Moscow also recently replaced its navy chief.

- 'Goal of destroying Kyiv' -

Ukraine's capital Kyiv and the western region of Lviv also came under a "massive" Russian air attack early Sunday, officials said, though no casualties were reported.

Ukraine's air force said Russia had fired 29 cruise missiles and 28 drones at its territory overnight.

It said it had downed 18 of the missiles and 25 drones.

Russia has significantly escalated its air attacks against Ukraine in recent days, in what it says is retaliation for a wave of Ukrainian strikes on its border regions.

In the early hours of Friday, Moscow launched its largest aerial barrages against Ukraine's energy sector since the start of the war, firing almost 90 missiles and 60 drones.

Russia has also resumed targeting Kyiv, carrying out its first strikes at the city since early February.

Russia "does not give up its goal of destroying Kyiv at any cost," Sergiy Popko, head of the city's military administration, said on Telegram.

- Polish airspace breach -

US Ambassador to Ukraine Bridget Brink also noted the increased frequency of recent attacks.

"Russia continues to indiscriminately launch drones and missiles with no regard for millions of civilians, violating international law," Brink wrote on X.

Poland's army said Sunday that one of the Russian missiles fired at western Ukraine had entered its airspace.

"Polish airspace was breached by one of the cruise missiles fired in the night by the air forces... of the Russian Federation," the army posted on X.

"The object flew through Polish airspace above the village of Oserdow (Lublin province) and stayed for 39 seconds," it said.

The country's Armed Forces Operational Command (RSZ) had said earlier that its forces were on a heightened state of readiness because of the "intensive long-range aviation activity of the Russian Federation tonight" and the missile attacks in Ukraine.

Poland, which has been a staunch ally of its neighbour Ukraine since Russia invaded in February 2022, said Sunday that it would demand an explanation from Moscow.

- Territorial gains -

On the battlefield, Russian forces are seeking to press their advantage in manpower and ammunition as Kyiv faces delays of additional Western aid.

Moscow claimed Saturday to have seized a village on the western outskirts of Bakhmut in eastern Ukraine.

Its capture last month of Adviivka, near the Russian-held stronghold of Donetsk, was the first major territorial gain made by Russia since the devastated city of Bakhmut was seized 10 months ago.

Russian President Vladimir Putin hailed that success as a sign that Russian forces were back on the offensive.