Ukraine says its forces hit a Russian ammunition depot in the Kherson region.

Ukrainian forces fighting to recapture territory in the south of the country said they had blown up a Russian ammunition depot in the Kherson region overnight, the latest in a series of missile attacks that Kyiv has claimed on Russian military infrastructure.

Officials loyal to the government in Moscow said the strike, in Nova Kakhovka, instead hit a warehouse containing saltpeter — sometimes used to make fertilizer or gunpowder — resulting in a large explosion that Russia said had damaged residential buildings, a hospital, a market and a humanitarian aid center. At least seven people were killed and dozens more wounded, the Russian state news agency Tass reported, citing a local official.

The competing claims could not be independently verified. Satellite imagery released on Tuesday morning by Planet Labs PBC, an American satellite imagery company, showed a notable impact crater where a missile appears to have struck, surrounded by destroyed buildings and warehouses.

Ukraine, seeking to spread Russian forces thin, has mounted limited attacks on Russian targets in the Kherson region while signaling that a wider counteroffensive is coming. On Sunday, the country’s deputy prime minister urged civilians to evacuate urgently. Increased Ukrainian missile strikes in recent days have forced Russian forces to focus on defensive positions, said the Institute for the Study of War, an American think tank, citing the Ukrainian military.

Vladimir Leontyev, the head of the Russia-installed Kakhovka District military-civilian administration in the Kherson region, said the weapon used in Nova Kakhovka was a High Mobility Artillery Rocket System, or HIMARS. Ukraine did not say what weapon was used in the attack.

The truck-mounted, multiple-rocket launchers are the most advanced weapons so far supplied by the United States to Ukraine. Both American and Ukrainian officials have said that the weapons are already making a notable impact on the battlefield, allowing Ukrainian forces to destroy Russian ammunition depots and command centers.

In the southern city of Mykolaiv, at least 12 people were injured on Tuesday morning by Russian shelling, according to Vitaliy Kim, the regional military governor.

Farther east, in Donetsk Province, where Moscow has focused its attention and where it has been making incremental gains, the body of a 9-year-old boy was pulled from the rubble of an apartment block hit late Saturday in the town of Chasiv Yar, Ukrainian officials said on Tuesday. In all, 45 people died in the attack, Ukrainian rescue officials said Tuesday, making it one of the deadliest in recent weeks.

In recent days, Russia has escalated its strikes on civilians in the province but has paused its operation to capture more territory there, according to military analysts.

Donetsk and the neighboring Luhansk Province make up the heavily industrial Donbas region, which has become the war’s main theater since Moscow failed in its attempts to seize the capital early in the conflict. Russian forces seized Luhansk this month after weeks of fighting.

Pavlo Kyrylenko, the Donetsk military governor, said on Tuesday on the Telegram social messaging app that 602 civilians had been killed there since the invasion began in February and that more than 1,500 people had been injured.