Russia and Ukraine targeted each other’s territory on Sunday with drone attacks and airstrikes that hit urban centers and energy facilities, as both sides look for ways to inflict damage beyond the battlefield.

The Russian military said it had shot down nearly 60 Ukrainian drones over the Krasnodar region of southwest Russia, which Ukraine has increasingly targeted in recent weeks because it is home to energy and military facilities supporting combat operations.

Local Russian officials said an oil refinery had been struck in the attack. A Ukrainian security official, speaking on condition of anonymity to discuss sensitive military matters, said Ukrainian drones had hit the refinery as well as a military airfield in the region. Russian officials did not comment on the reported strike on the airfield.

Ukrainian officials said Russia struck northeast Ukraine, including the city of Kharkiv, killing at least 10 civilians and wounding more than 20 people. Russia has not commented on the strikes, which could not be independently confirmed. Kharkiv, Ukraine’s second largest city, has been pounded by Russian missiles in recent months, in what military experts say is a Russian tactic intended to create panic and force residents to flee.

Strikes on logistical hubs and troop concentrations deep behind enemy lines have been a constant in this war. But it has become all the more important for Ukraine as it seeks to relieve troops who are struggling to contain Russian advances on the ground by disrupting Moscow’s military operations.

Since the fall, Russia has had the upper hand on the battlefield, allowing it to launch assaults on different parts of the more than 600-mile front line to probe and break through Ukrainian defenses. Most recently, it has opened a new front in Ukraine’s northeast, near Kharkiv, quickly capturing several settlements and forcing the Ukrainian army to redeploy units there from other battlefield hot spots.

Now, Russia is looking to make the most of the situation by breaking through the thinned-out Ukrainian lines.

Ukraine’s General Staff reported more than 80 Russian attacks occurred on Saturday. Many of them took place in the southeastern Donetsk region, which Russia annexed in 2022 but does not fully control. In particular, Ukraine’s military said it had repelled a large Russian attack involving tanks on Chasiv Yar, a Ukrainian stronghold that is one of Russia’s main targets in the Donetsk region.

Over months of bloody assaults, Russia has gradually clawed back at Ukrainian land. Pasi Paroinen, an analyst from the Finnish Black Bird Group, which analyzes satellite images and combat footage from the battlefield, said that Russia had gained more territory so far this year than it lost during Ukraine’s summer counteroffensive last year.

Part of Ukraine’s strategy to disrupt this slow but steady advance has been a sustained air campaign against Russian facilities that supply fuel and other refined oil products to tanks, ships and fighter jets.

On Sunday, six Ukrainian drones struck an oil refinery in Slavyansk, in Russia’s Krasnodar region, forcing the plant to halt operations, according to TASS, Russia’s state news agency.

The campaign also appears intended to undermine the Russian energy industry, which it at the core of Russia’s economy and war effort. The United States said in a report released last week that the strikes had “disrupted about 14 percent of Russia’s oil refining capacity” and that by mid-March, domestic gasoline and diesel prices had risen by 20 to 30 percent in Russia. The report only covered a two-month period from late January to late March.

Russia also said on Sunday that it had intercepted nine Ukrainian missiles heading toward Crimea, the Ukrainian peninsula that Moscow illegally annexed in 2014. Moscow has turned the peninsula into a military logistics hub to funnel troops and ammunition to the battlefield in the south. It has also been used as a launchpad for drone and missile attacks.