KYIV, May 23 - Russian missiles slammed into Ukraine’s second-largest city in the country’s northeast and killed at least seven civilians early Thursday, officials said, as Kyiv’s army labored to hold off an intense cross-border offensive by the Kremlin’s larger and better-equipped forces.

At least 20 people were wounded as S-300 missiles struck the city of Kharkiv, regional Gov. Oleh Syniehubov said. Explosions reverberated around the city of some 1 million people, The Associated Press reported.

President Volodymyr Zelenskyy called the attack “extremely cruel” and expressed renewed frustration at not getting enough air defense systems from the country’s Western partners to prevent the barrages after more than two years on unrelenting war.

The city of Kharkiv, which is the capital of the region of the same name, is about 20 kilometers (12 miles) from the Russian border. Moscow’s troops have in recent weeks captured villages in the area as part of a broad push, and analysts say they may be trying to get within artillery range of the city.

The Russian push is shaping up to be Ukraine’s biggest test since Moscow’s full-scale invasion in February 2022, with outnumbered and outgunned Ukrainian forces being pressed at several points along the about 1,000-kilometer (600-mile) front line that snakes from north to south in eastern Ukraine.

With Kyiv short of air defenses and waiting for more Western military support that only recently started trickling in, Ukraine’s army has been pushed back in places while Russia has pounded its power grid and civilian areas. Kyiv endured further power outages on Thursday.

Ukrainian Foreign Minister Dmytro Kuleba said the attacks underscored the country’s “urgent” need for more U.S.-made Patriot systems to defend its skies.

Germany recently pledged one of the missile systems “but getting six more as soon as possible remains critical not only for Ukraine’s survival but for peace in Europe,” Kuleba wrote on the social media platform X.

The United States is expected to announce an additional $275 million in military aid for Ukraine on Friday, two U.S. officials told The Associated Press, speaking on condition of anonymity to provide details of the support before the public announcement.

But no air defense systems appear to be included in the package containing high mobility artillery rocket systems, or HIMARS, as well as essential 155 mm and 105 mm artillery rounds.

Zelenskyy said the main hotspots in recent fighting have been Kharkiv and the neighboring Donetsk region, where Ukraine’s defenders withdrew in February from the stronghold of Avdiivka. For the Kremlin, taking control of all of partially occupied Donetsk is a war priority.

At the same time, and in an apparent effort to stretch Ukraine’s depleted forces, Russian troops have made incursions in the northern Sumy region.

Nearly 1,500 people, including 200 children, have been evacuated from the towns of Bilopillia and Vorozhba there, according to regional Gov. Volodymyr Artiukh.

“The main focus (of the fighting) is on the entire border area,” Zelenskyy said in his nightly video address Wednesday.

In Liubotyn, a small town about 10 kilometers (6 miles) west of the city of Kharkiv, Russian missiles struck the town’s center, wounding eight civilians. In Derhachi, another nearby town, 13 people were wounded in another aerial strike, authorities said. (ap/ez)