Russian forces have started to storm the last pocket of resistance in Mariupol, the Azovstal steelworks, some Ukrainian defenders of the plant say.
The move comes almost two weeks after Russian President Vladimir Putin ordered his military not to storm the plant, but rather block it off.
Deputy commander of the Azov Regiment, Sviatoslav Palamar, confirmed the situation when he was asked about local media reports on the attack.
Earlier on Tuesday, Mariupol patrol police chief Mykhailo Vershinin was quoted by Ukrainian television as saying that the Russian military "have started to storm the plant in several places".
Denys Shlega, a commander of a brigade of Ukraine's National Guard at Azovstal, said "the enemy is trying to storm the Azovstal plant with significant forces using armoured vehicles".
Even before word came that Russian forces were storming the plant, the military said it was bombarding it after Vadim Astafyev, a Russian Defence Ministry spokesman, said that Ukrainian fighters used the ceasefire that allowed civilians to flee to take up new positions.
They “came out of the basements, took up firing positions on the territory and in the buildings of the plant,” he said.
Russian troops along with the Moscow-backed separatist forces used "artillery and aircraft... to destroy these firing positions".
More than 200 civilians remain in the Azovstal steel plant, according to Mariupol Mayor Vadym Boichenko, with a total of 100,000 civilians still in the city that has been devastated by weeks of Russian siege and shelling.
The reports come amid a UN effort that evacuated at least 101 people from the plant to Zaporizhzhia on Monday.
Osnat Lubriani, the humanitarian coordinator for the UN in Ukraine, said that those evacuated "could finally leave the bunkers below the Azovstal steelworks and see the daylight after two months".
Another 58 people joined the convoy in Manhush, a town on the outskirts of Mariupol.
After failing to take Kyiv in the early weeks of the war, Russia withdrew some of its forces and then said it would switch its focus to Ukraine’s eastern industrial heartland of the Donbas.
Mariupol lies in the region, and its capture would deprive Ukraine of a vital port, allow Russia to establish a land corridor to the Crimean Peninsula, which it seized from Ukraine in 2014, and free up troops for fighting elsewhere in the Donbas.
'We had said goodbye to life'
Dozens of evacuees who took refuge for weeks in the bunkers of the steel works reached the safety of Kyiv-controlled Zaporizhzhia on Tuesday.
Exhausted-looking people, including young children and pensioners laden with bags, clambered off buses that pulled into a car park in south-eastern Ukraine after escaping the ruins of their hometown where Russia now claims control.
"We had said goodbye to life, we didn't think anyone knew we were there," said 70-year-old Valentina Sytnykova, who sheltered in the steelworks for two months with her son and 10-year-old granddaughter.
The sprawling complex and its bunkers and tunnels became a refuge for both civilians and Ukrainian fighters as Moscow laid siege to Mariupol.
Ms Sytnykova said that 17 other families, including children, had sheltered with her and that their bunker had collapsed around them as Russia bombarded the area.
Ukrainian soldiers pulled them out of the rubble three days ago.
"I can't believe I made it, we just want rest," said Alina Kozitskaya, who spent weeks sheltering in a basement with her bags packed waiting for a chance to escape.
A few women held up handmade signs, calling on Ukrainian authorities to evacuate the soldiers — their relatives and loved ones — who are still trapped in Azovstal and encircled by Russian forces.
"We're scared that after the evacuation of civilians, the guys will be left there." said Ksenia Chebysheva, 29, whose husband is among the Azov Regiment servicemen there.
Ms Chebysheva, who held up a sign saying "Save the Military from Azovstal", said she had heard her husband was still alive on April 26 but had not had any news since.
"They're forgotten by everyone."
Shelling too intense to recover bodies
The north-eastern city of Kharkiv, Ukraine's second-largest city, was under bombardment, as it has been since the early days of the invasion, the Ukrainian military said on Tuesday.
Giving an early update on battlefront, Ukraine's general staff said its forces were defending the approach to Kharkiv from Izyum, a town on the Donets river, some 120 kilometres to the south-east, as Russian forces left a trail of destruction in Luhansk province.
Ukraine's military said Russian forces were trying to take the frontline Luhansk province town of Rubizhne and prepare an assault on nearby Sievierodonetsk.
The heaviest clashes were taking place around Popasna, farther south.
Shelling was so intense it was not possible to collect bodies, said regional Governor Serhiy Gaidai.
"I don't even want to speak about what's happening with the people living in Popasna, Rubizhne and Novotoshkivske right now. These cities simply don't exist anymore. They have completely destroyed them," he said.
Russian troops are now trying to encircle a large Ukrainian force there, attacking from three directions with massive bombardment along the front.
At least nine civilians were killed by Russian fire in the Donetsk region of eastern Ukraine on Tuesday, the regional governor said.
Donetsk Governor Pavlo Kyrylenko wrote on the Telegram messaging app that at least three civilians had been killed during an aerial bombardment of the town of Avdiivka.
Three more were killed by shelling of the city of Vuhledar and three were killed in shelling of the town of Lyman, he wrote.
Some other areas of Donetsk were under constant fire and regional authorities were trying to evacuate civilians from frontline areas.
Reuters could not independently verify Ukraine's battlefield accounts.
Germany ready to back Russian oil embargo
In Brussels, the European Commission is expected to propose a sixth package of EU sanctions this week against Russia, including a possible embargo on buying Russian oil.
The sanctions will target Moscow's oil industry, more Russian banks and those responsible for disinformation, the EU's top diplomat said.
The latest round of sanctions would also affect Sberbank, Russia's top lender, diplomats said, adding it to several banks that have already been excluded from the SWIFT messaging system.
Kyiv said Russia's energy exports to Europe, so far largely exempt from international sanctions, are funding the Kremlin war effort with millions of euros every day.
"This package should include clear steps to block Russia's revenues from energy resources," Ukrainian President Volodymyr Zelenskyy said in his nightly video address.
Officials said European Commission President Ursula von der Leyen is expected to spell out the proposed new sanctions on Wednesday, and that they would include a ban on imports of Russian oil by the end of this year.
Germany said on Monday it was prepared to back an immediate EU embargo on Russian oil.
Chancellor Olaf Scholz, who has been more cautious than other Western leaders in backing Ukraine, has been under growing pressure to take a firmer line.
Mr Scholz vowed sanctions will not be lifted until Mr Putin signs a peace deal with Ukraine that Kyiv can support, he said in an interview with ZDF public television.
ABC/Wires
