KRAMATORSK, Ukraine (AP) — Officials at a vocational school in an eastern Ukraine city dismissed claims by Russia that hundreds of Ukrainian troops were killed in a missile strike there, saying Monday that a rocket merely blew out windows and damaged classrooms.

Russia specifically named the vocational school in Kramatorsk as the target of an attack in the almost 11-month war. The Russian Defense Ministry said its missiles hit two temporary bases housing 1,300 Ukrainian troops in the city, killing 600 of them, late Saturday.

Associated Press reporters visiting the scene in sunny weather Monday saw a four-story concrete building with most of its windows blown out. Inside, locals were cleaning up debris, sweeping up broken glass and hurling broken furniture out into a missile crater below.

A separate, six-story school building was largely undamaged. There were neither signs of a Ukrainian military presence nor any casualties.

Yana Pristupa, the school’s deputy director, scoffed at Moscow’s claims of hitting troop concentration.

“Nobody saw a single spot of blood anywhere,” she told the Associated Press. “Everyone saw yesterday that no one carried out any bodies. It’s just people cleaning up.”

She said that before the war began last February the school had more than 300 students, most of them studying mechanical engineering, with most lessons moving online when Russia invaded.

The students “are now in shock,” she said, adding, “What a great facility it was.”

Ukrainian officials on Sunday quickly denied the Russian claims it had lost a large number of soldiers in the attack.

Despite the absence of any evidence, Kremlin spokesman Dmitry Peskov said reports from the scene didn’t shake senior officials’ faith in defence authorities.

“The Defense Ministry is the main, legitimate and comprehensive source of information about the course of the special military operation,” Peskov said Monday in a conference call with reporters, using the Kremlin’s term for the war.

Both sides have regularly claimed killing hundreds of each other’s soldiers in attacks. The claims can seldom be independently verified because of the fighting.

Moscow’s allegations may have backfired domestically, however, as some Russian military bloggers criticised them.

The Institute for the Study of War think tank said the bloggers “responded negatively to the Russian (Ministry of Defense’s) claim, pointing out that the Russian MoD frequently presents fraudulent claims and criticising Russian military leadership for fabricating a story … instead of holding Russian leadership responsible for the losses accountable.”

A Russian Defense Ministry spokesman said the strikes on Kramatorsk were in retaliation for Ukraine’s attack in Makiivka on New Year’s Eve, in which at least 89 Russian soldiers gathered at a temporary barracks died, according to Moscow. Ukrainian authorities said hundreds were killed.

It was one of the deadliest attacks on the Kremlin’s forces since the war began more than 10 months ago and an embarrassing loss.

Such revenge strikes have occurred before. When Ukraine in early October struck a bridge linking the Russian-occupied Crimean Peninsula with Russia, damaging an important supply artery for the Kremlin’s faltering war effort in southern Ukraine and hitting a key symbol of Russian power in the region, the Kremlin sent a first massive barrage against Ukraine’s energy facilities. It was billed as retaliation for the bridge attack and heralded a period of relentless bombardments against Ukraine’s energy infrastructure.

Ukraine’s deputy defence minister said Monday that Russian forces have launched a fresh assault on the town of Soledar in the eastern Donetsk region. Taking Soledar would allow Russia to intensify its attacks on the strategically key city of Bakhmut, where intense fighting has destroyed an estimated 60 per cent of buildings.

Ukraine’s presidential office reported Monday that at least three civilians were killed and 12 others wounded over the previous 24 hours as nine Ukrainian regions in the southeast of the country were shelled.

In one attack on Monday, two people were killed and five others, including a 13-year-old girl, were wounded by a Russian rocket strike that hit a village market in the northeastern Kharkiv region, Ukrainian officials said.

Kharkiv regional Governor Oleh Syniehubov said the strike hit Shevchenkove village. Photos on his Telegram channel showed ruined pavilions, some of them still on fire, and rubble all around them.

According to Ukrainian officials, more people could be trapped under the rubble. A rescue operation to find them was underway.

Russia maintains it is fighting against the might of NATO, not just the Ukrainians.

Nikolai Patrushev, the secretary of Russia’s Security Council, repeated that argument in an interview published Monday, saying that “the events in Ukraine aren’t a clash between Moscow and Kyiv, it’s a military confrontation between NATO, and particularly the U.S. and Britain, with Russia.”

“The sooner the citizens of Ukraine realise that the West is fighting Russia with their hands, the more lives will be saved,” Patrushev said in an interview with Argumenty i Fakty.

Meanwhile, two UK citizens working as volunteers in eastern Ukraine have disappeared, the Ukrainian national police said Monday.

Andrew Bagshaw and Christopher Perry left Kramatorsk on Friday bound for Soledar, where heavy fighting was reported, and contact with them was lost, police said.

Bagshaw, a resident of New Zealand, was in Ukraine to assist in delivering humanitarian aid, according to New Zealand media reports.