Rescuers are seeking to evacuate more civilians from tunnels beneath a steel mill in Mariupol as Ukrainian fighters make their last stand to prevent Russian troops from completing their takeover of the strategically important port city.

Dozens of people were evacuated on Friday from the Azovstal plant and handed over to representatives of the United Nations and the International Committee of the Red Cross, Russian and Ukrainian officials said.

The Russian military said the group of 50 included 11 children.

Woman leaves shelter
A woman who left a shelter in the Metallurgical Combine Azovstal walks to a bus escorted by a serviceman of Donetsk People’s Republic militia in Mariupol (AP)

Russian officials and Ukrainian deputy prime minister Iryna Vereshchuk said the evacuation efforts would continue into the weekend.

The latest evacuees followed roughly 500 other civilians who got out of the plant and city in recent days.

The fight for the last Ukrainian stronghold in a city reduced to ruins by the Russian onslaught appears increasingly desperate.

There is growing speculation that President Vladimir Putin wants to finish the battle for Mariupol so he can present a triumph to the Russian people in time for Monday’s Victory Day, the biggest patriotic holiday on the Russian calendar.

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A man and a girl leaving Mariupol escorted by forces of the government of the Donetsk People’s Republic (AP)

As the holiday commemorating the Soviet Union’s victory over Nazi Germany in the Second World War approaches, cities across Ukraine are preparing for an expected increase in Russian attacks, with officials urging residents to heed air raid warnings.

“These symbolic dates are to the Russian aggressor like red to a bull,” said Ukraine’s first deputy interior minister, Yevhen Yenin.

“While the entire civilised world remembers the victims of terrible wars on these days, the Russian Federation wants parades and is preparing to dance over bones in Mariupol.”

Ukrainian President Volodymyr Zelensky also reminded people not to go into forests that were recently under Russian occupation because many land mines and trip wires remain in place.

Refugees in Ukraine
A woman holds up a baby as a family who fled from Enerhodar is reunited upon their arrival to a reception centre for displaced people in Zaporizhzhia, Ukraine (AP)

On Saturday, a Russian missile destroyed a Ukrainian national museum dedicated to the life and work of an 18th-century philosopher, the local council said. It posted photographs on Facebook showing the Gregory Skovoroda museum engulfed in flames.

As an indication of his importance to Ukraine’s cultural heritage, Skovoroda’s likeness adorns a Ukrainian banknote.

The museum in Skovorodynivka lies near the Russian border in the Kharkiv region where fighting has been fierce.

By Russia’s most recent estimate, roughly 2,000 Ukrainian fighters are holed up in the vast maze of tunnels and bunkers under the Azovstal steelworks. They have repeatedly refused to surrender.

Ukrainian officials said before Friday’s evacuations that a few hundred civilians were also trapped there, and fears for their safety have increased as the battle has grown fiercer in recent days.

Kateryna Prokopenko, whose husband, Denys Prokopenko, commands the Azov Regiment troops inside the plant, issued a desperate plea to also spare the fighters.

She said they would be willing to go to a third country to wait out the war but would never surrender to Russia because that would mean “filtration camps, prison, torture and death”.

If nothing is done to save her husband and his men, they will “stand to the end without surrender”, she told The Associated Press on Friday.

Kateryna Prokopenko
Kateryna Prokopenko tries to speak with her husband Denys Prokopenko, commander of the Azov regiment (AP)

Mr Zelensky said “influential states” are involved in efforts to rescue the soldiers, although he did not mention any by name.

“We are also working on diplomatic options to save our troops who are still at Azovstal,” he said in his nightly video address.

UN officials have been tight-lipped about the civilian evacuation efforts, but it seemed likely that the latest evacuees would be taken to Zaporizhzhia, a Ukrainian-controlled city about 140 miles north-west of Mariupol where others who escaped the port city were brought.

Some of the plant’s previous evacuees spoke to the AP about the horrors of being surrounded by death in the moldy, underground bunker with little food and water, poor medical care and diminishing hope. Some said they felt guilty for leaving others behind.

Rubble and wreckage
The gutted remains of the Antonov An-225, the world’s biggest cargo aircraft, and Russian military vehicles destroyed during recent fighting between Russian and Ukrainian forces, at the Antonov airport in Hostomel, on the outskirts of Kyiv (AP)

Russian forces have struggled to make significant gains elsewhere, 10 weeks into a devastating war that has killed thousands of people, forced millions to flee the country and flattened large swaths of cities.

Ukrainian officials said the risk of massive shelling increased ahead of Victory Day.

Kyiv Mayor Vitali Klitschko said authorities would reinforce street patrols in the capital.

Ukraine’s southern Odesa region, which was the target of two missile attacks on Friday, is to adopt a curfew.

The Ukrainian military’s general staff said that its forces repelled 11 attacks in the Donbas region and destroyed tanks and armoured vehicles, further frustrating Mr Putin’s ambitions after his abortive attempt to seize Kyiv. Russia made no acknowledgement of the losses.

The Ukrainian army also said it made progress in the north-eastern Kharkiv region, recapturing five villages and part of a sixth.

Meanwhile, one person was reported dead and three more were wounded Friday as a result of Russian shelling in Lyman, a city in Ukraine’s eastern Donetsk region.

The fall of Mariupol would deprive Ukraine of a vital port. It would also allow Russia to establish a land corridor to the Crimean Peninsula, which it seized from Ukraine in 2014, and free some Russian troops to fight elsewhere in the Donbas, the eastern industrial region that the Kremlin says is now its chief objective.

The city’s capture also holds symbolic value since it has been the scene of some of the worst suffering of the war and a surprisingly fierce resistance.