KYIV, Ukraine — Russia attacked the Ukrainian president’s hometown with suicide drones on Sunday, and Ukraine pushed ahead with its counteroffensive after taking back control of a strategic eastern city.

Russia’s loss of Lyman, which it had been using as a transport and logistics hub, is a new blow to the Kremlin as it seeks to escalate the war by illegally annexing four regions of Ukraine.

“The Ukrainian flag is already in Lyman,” Ukrainian President Volodymyr Zelenskyy said in his nightly address. “Over the past week, there have been more Ukrainian flags in the Donbas. In a week there will be even more.”

In southern Ukraine, Zelenskyy’s hometown Krivyi Rih came under Russian attack by a suicide drone that struck a school early Sunday and destroyed two stories of it, said Valentyn Reznichenko, the governor of Ukraine’s Dnipropetrovsk region.

A fire sparked by the drone attack has been put out, he said.

Russia in recent weeks has begun using Iranian-made suicide drones to attack targets in Ukraine. In southern Ukraine, the Ukrainian air force said it shot down five Iranian-made drones overnight, while two others made it through air defenses.

Meanwhile, Russian attacks also targeted the city of Zaporizhzhia, authorities said Sunday.

Ukraine’s military said Sunday it carried out a strike on a Russian ammunition depot in the country’s south, in Chernihiv, and hitting other Russian command posts, ammunition depots and two S-300 anti-aircraft batteries.

The reports of military activity couldn’t be immediately verified.

After being encircled by Ukrainian forces, Russia pulled troops out Saturday from Lyman in the east in what the British military described as a “significant political setback” for Moscow. Taking the city paves the way for Ukrainian troops to potentially push farther into territory Russia has occupied.

Lyman had been an important link in the Russian front line for ground communications and logistics. Lyman is in the Donetsk region near the border with Luhansk, two regions that Russia annexed Friday after forcing the population to vote in referendums at gunpoint.

Russia’s Defense Ministry claimed to have inflicted damage on Ukrainian forces in battling to hold Lyman, but said outnumbered Russian troops were withdrawn to more favorable positions.

In a daily intelligence briefing, the British Defense Ministry called Lyman crucial because it has “a key road crossing over the Siversky Donets River, behind which Russia has been attempting to consolidate its defenses.”

The British said they believed that the city had been held by “undermanned elements” prior to the Russian withdrawal.

Moscow’s withdrawal from Lyman prompted immediate criticism from some Russian officials.

“Further losses of territory in illegally occupied territories will almost certainly lead to an intensification of this public criticism and increase the pressure on senior commanders,” the British military briefing said.

Ukrainian forces have retaken swaths of territory in a counteroffensive that started in September and has humiliated and angered Russia.

Russian President Vladimir Putin frames the Ukrainian gains as a U.S.-orchestrated effort to destroy Russia and this week heightened threats of nuclear force in some of his toughest, most anti-Western rhetoric to date.