(NewsNation) — Ukraine’s armed forces command observed Monday signs that Russia is starting an anticipated new offensive in the east of the country, increasing the intensity of attacks in parts of the Donetsk and Kharkiv regions.

The news comes as Russian shelling killed at least seven in Lviv. Lviv’s regional governor, Maksym Kozytskyy, said Monday seven people were killed and another eight, including a child, were wounded by four Russian missile strikes. He said three hit military infrastructure facilities and one struck a tire shop. He said emergency teams were putting out fires caused by the strikes.

Lviv Mayor Andriy Sadovyi put the toll at seven dead and 11 wounded, including one child.

Still, more than two months into the war, Ukrainian President Volodymyr Zelenskyy has vowed to “fight absolutely to the end.”

Military analysts suggest Russia is increasing its strikes on weapons factories, railways and other infrastructure targets across Ukraine to wear down the country’s ability to resist a major ground offensive in the Donbas, Ukraine’s eastern industrial heartland.

With missiles and rockets battering various parts of the country, Zelenskyy has accused Russian soldiers of torture and kidnappings in areas they control.

Ukraine’s government halted civilian evacuations for a second day on Monday, saying Russian forces were shelling and blocking the humanitarian corridors.

Deputy Prime Minister Iryna Vereshchuk said Ukraine had been negotiating passage from cities and towns in eastern and southeastern Ukraine, including Mariupol and other areas in the Donbas. The government of the Luhansk region in the Donbas said four civilians trying to flee were shot dead by Russian forces.

The fall of Mariupol, which has been reduced to rubble in a eight-week siege, would give Moscow its biggest victory of the war. But Ukraine soldiers are fighting back by holding on to the giant, 4-square-mile Azovstal steel mill.

Many Mariupol civilians, including children, are also sheltering at the Azovstal plant, Mikhail Vershinin, head of the city’s patrol police, told Mariupol television. He said they are hiding from Russian shelling and from Russian soldiers.

Capturing the city on the Sea of Azov would free Russian troops for a new offensive to take control of the Donbas. It would also allow Russia to secure a land corridor to the Crimean Peninsula, which it seized from Ukraine in 2014, and it would deprive Ukraine of a major port and prized industrial assets.

“We are doing everything to ensure the defense” of eastern Ukraine, Zelenskyy said in an overnight address.

The nonstop shelling and fighting has killed at least 21,000 people, according to Ukrainian estimates. An estimated 100,000 people remained in the city out of a prewar population of 450,000, trapped without food, water, heat or electricity.

Russian forces, meanwhile, carried out aerial attacks near Kyiv and elsewhere in an effort to weaken Ukraine’s military capacity ahead of the anticipated assault on the Donbas. After the humiliating sinking of the flagship of Russia’s Black Sea Fleet last week in what the Ukrainians boasted was a missile attack, the Kremlin had vowed to step up strikes on the capital.

Russia said Sunday that it had attacked an ammunition plant near Kyiv overnight with precision-guided missiles, the third such strike in as many days. Explosions were also reported in Kramatorsk, the eastern city where rockets earlier this month killed at least 57 people at a train station crowded with civilians trying to evacuate ahead of the Russian offensive.

At least five people were killed by Russian shelling in Kharkiv on Sunday, regional officials said.

Kharkiv Mayor Igor Terekhov, in an impassioned address marking Orthodox Palm Sunday, lashed out at Russian forces for not letting up the bombing campaign on such a sacred day.

As the fight moves on, Zelenskyy urged the world to send more weapons and apply tougher sanctions against Moscow. Russian President Vladimir Putin has vowed to see the war through until his goal is met. To date, peace talks have been unsuccessful.