KYIV, Ukraine (AP) – The key eastern Ukraine city of Pokrovsk is without a drinking water supply or natural gas for cooking and heating, authorities said Thursday, as the Russian army´s attritional slog across the Donetsk region lays waste to public infrastructure and forces civilians to flee their homes.

A water filtration station in Pokrovsk was damaged in recent fighting, and more than 300 hastily drilled water wells are the city´s last source of drinking water, Donetsk regional Gov. Vadym Filashkin said.

The previous day, Russians destroyed a natural gas distribution station near Pokrovsk, Filashkin said. Some 18,000 people remain in the city, including 522 children, he said. More than 20,000 people have left in the past six weeks as Russian forces creep closer to residential areas, Filashkin said.

“Evacuation is the only … choice for civilians,” he added.

Pokrovsk is one of Ukraine´s main defensive strongholds and a key logistics hub in the Donetsk region, which lies on part of the 1,000-kilometer (600-mile) front line. Its capture would compromise Ukraine´s defensive abilities and supply routes and would bring Russia closer to its stated goal of capturing the entire Donetsk region, which it partially occupies.

Russian troops backed by artillery and powerful glide bombs have turned Donetsk cities and towns such as Bakhmut and Avdiivka into bombed-out shells, though the push has cost Russia heavily in troops and armor.

Ukrainian forces have held out as long as possible, even when strongholds such as Chasiv Yar appeared to be in danger of imminent collapse. Ukraine has also launched a daring incursion into Russia´s Kursk region, partly in the hope that Russia will divert its troops there from Donetsk.

But Russian Maj. Gen. Apti Alaudinov said troops had recaptured 10 settlements in Kursk and caused the Ukrainian army heavy losses, Russian state news agency Tass reported Thursday. It was not possible to independently verify the claim.

Russia has fired missile and drone barrages at Ukraine just about every day since the war began in February 2022, aiming especially at the power grid and potentially dooming Ukrainians to a bitterly cold winter this year.

The United States and Britain pledged nearly $1.5 billion in additional aid to Ukraine on Wednesday during a visit to Kyiv by their top diplomats. Much of that will go to restoring the electricity supply.

U.S. Secretary of State Antony Blinken said, “we´re again seeing Putin dust off his winter playbook, targeting Ukrainian energy and electricity systems to weaponize the cold against the Ukrainian people.”

An overnight drone attack on Konotop, a town in Ukraine´s northern Sumy region, largely knocked out the electricity supply, regional officials said.

The blasts also blew out an “incredibly high number” of windows in the city and damaged many of the town´s tram tracks, Mayor Artem Semenikhin said.

Russia launched a total of 64 Shahed drones and five missiles over eastern, central, and northern regions of Ukraine, Ukraine´s air force said in its Thursday morning report.

Ukraine has expressed frustration that its Western partners won´t let it use sophisticated modern weapons they supply to hit places inside Russia where the missiles and drones are launched from. Some Western leaders fear that would trigger an escalation of the war.

But after Iran recently supplied ballistic missiles to Russia, according to the U.S., those rules of engagement could be set to change in coming days as heavier Russian bombardments could swamp Ukraine´s meager air defenses.

In other developments, Ukrainian Military Intelligence claimed to have shot down a Russian Su-30SM jet over the Black Sea.

A post on the agency´s social media Thursday said the warplane was hit with a portable surface-to-air missile.