KRAMATORSK, Ukraine (AP) - Russia redoubled its push for Ukraine's eastern Donbas region Wednesday, with the Ukrainian military claiming to have repelled some advances and both sides reporting casualties.

The Ukrainian armed forces General Staff said troops stopped enemy units advancing towards Sloviansk, a city in Donetsk, one of two provinces in the Donbas whose capture is among Moscow's main goals. It also claimed to have repelled Russian attacks on a town and village north of Ukraine's second city, Kharkiv, just miles (kilometers) from the Russian border.

The Ukrainian presidential office said most civilian casualties were in Donetsk province, where Gov. Pavlo Kyrylenko said two people died in the city of Avdiivka; the cities of Sloviansk, Krasnohorivka and Kurakhove each reported one civilian killed.

“Every crime will be punished,” he wrote on social media.

Kyrylenko urged the province's more than 350,000 remaining residents to flee late Tuesday, saying that evacuating Donetsk was necessary to save lives and allow the Ukrainian army to put up a better defense against the Russian advance.

Donetsk is part of the Donbas, a mostly Russian-speaking industrial area where Ukraine's most experienced soldiers are concentrated. Pro-Russian separatists have fought Ukrainian forces and controlled much of the Donbas for eight years.

Before Russia invaded Ukraine on Feb. 24, Russian President Vladimir Putin recognized the independence of Donetsk and Luhansk, the two self-proclaimed separatist republics. Putin on Monday declared the complete seizure of Luhansk, after Ukrainian troops withdrew from the last city under their control in the province.

Luhansk Gov. Serhiy Haidai denied Wednesday that the Russians had completely captured the province. Heavy fighting continued in villages around Lysychansk, the city Ukrainians soldiers withdrew from and which Russian troops took Sunday, he said.

“The Russians have paid a high price, but the Luhansk region is not fully captured by the Russian army,” Haidai said. “Some settlements have been overrun by each side several times.”

He accused Russian forces of scorched earth tactics, “burning down and destroying everything on their way.”

The Russian military pounded Luhansk for weeks from the air and ground, causing mass destruction and large civilian casualties. When Russian troops enter villages and cities, they are largely empty. From pre-war populations each of around 100,000, only up to 15,000 residents remain in Lysychansk and some 8,000 in the nearby city of Sievierodonetsk, which Russian and separatist fighters seized last month, Haidai said.

Ukrainian President Volodymr Zelenskky, in his nightly video address Wednesday, said that of all the battles in his country, “the most brutal confrontation” is raging in the Donbas.

The Associated Press on Wednesday saw the bloody aftermath of one attack in the rebel-held Donetsk town of Makiivka and spoke to eyewitnesses who said a Soviet-era missile struck a playground outside a residential home. Local separatists blamed the attack on Ukrainian forces.

Blood stained the seat of a swing and pooled on the ground below. Russian media cited the separatists as saying two children were killed and three children and two adults were wounded.

“The boy was lying on the swings like this and I saw he had blood coming out from this side,” said resident Svetlana Lyga. “I did not come close … I simply couldn't. The girl was taken by the ambulance. She was alive at that moment.”

North of Donetsk, Russian forces hit Kharkiv with missile strikes overnight. Kharkiv regional Gov. Oleh Syniehubov said Wednesday on Telegram that one person was killed and three, including a toddler, were injured. First responders crunched through the debris of a Kharkiv university, where Zelenskyy said the main building, lecture halls, museum and library were destroyed.

“When it comes to the definition of barbarism, this strike fits the bill the most,” the Ukrainian president said in his nightly address. “Only an enemy of civilization and humanity can do such things - strike missiles at a university, a pedagogical university.”

The attacks indicated that residents of the city are unlikely to enjoy calm as the war grinds into its fifth month.

Providing its account of the fighting in Kharkiv, Russia's Defense Ministry said its forces killed up to 100 Ukrainian troops and destroyed four armored vehicles. The ministry also said its forces struck a Ukrainian air-defense radar and camp housing foreign fighters in southern Ukraine's Mykolaiv region.

The ministry's chief spokesman, Igor Konashenkov, claimed air-launched high precision missiles destroyed two HIMARS multiple-launch rocket systems the U.S. had sent to Ukraine. The Ukrainian military denied Moscow's claims.

Elsewhere on the battlefield:

- Russian rocket strikes wounded four people in the town of Pokrovska in Ukraine's eastern Dnipropetrovsk region, Gov. Valentyn Reznichenko wrote on Telegram. He added that four settlements to the west came under relentless shelling Wednesday, burning wheat fields, damaging a solar power plant and destroying a house.

- In southern Ukraine, a local official said one person died and four were wounded in a blast in a Russian-occupied town, Skadovsk. Mayor Oleksandr Yakovlev told the Suspilne broadcaster a child was among those injured in an explosion that tore through a residential building.

- Russian state media claimed Wednesday that an oil refinery in Donetsk had caught fire due to Ukrainian shelling. The Tass news agency cited a separatists' claim that the refinery fire was one of 27 Ukrainian attacks on Donetsk over the previous 24 hours. Ukrainian authorities didn't immediately confirm the attack.

In other developments:

- European Commission President Ursula von der Leyen said the 27-nation European Union needs to make emergency plans to prepare for a complete cut-off of Russian gas. The EU has already imposed sanctions on Russia, including on some energy supplies, and is trying to find other sources. But von der Leyen said the bloc needed to be ready for shock disruptions from Moscow.

- European Union lawmakers voted to support a plan by the bloc's executive commission to include natural gas and nuclear power on its list of sustainable activities. Environmentalists accused the EU of “greenwashing.” One argument for rejecting the proposal was that it could boost gas sales that benefit Russia. The European Commission said the Ukrainian government backs its stance.

- A court in Russia ordered a pipeline bringing oil from Kazakhstan to Europe halted for 30 days for what it said were environmental violations, Russian media reported.

- Russian food bound for an Arctic coal mining settlement have resumed transiting via mainland Norway after weeks of tension, a Russian representative said Wednesday. Russian officials had accused Oslo of blocking a shipment of essential goods for Russian miners in Barentsburg, on the far-Northern Svalbard archipelago.

- A top Russian official warned the United States could face the “wrath of God” if it works to help establish an international tribunal to investigate Russia's actions in Ukraine. Dmitry Medvedev, the deputy secretary of Russia's Security Council, denounced the U.S. for what he described as its efforts to “spread chaos and destruction across the world for the sake of `true democracy.”'

Murru and Cara Anna contributed from Kharkiv.