Ukrainian President Volodymyr Zelenskyy has claimed that Moscow bombarded a boarding school in Ukrainian-occupied Russia.

According to reports, civilians were sheltering in the region.

The Ukrainian army was quoted as saying by BBC that four people were killed and dozens - many of them elderly - were injured in the town of Sudzha in the Kursk region, which has been under Ukrainian control for five months.

Over 80 people have been rescued from the building.

In an X post, Zelenskyy said: "This is how Russia wages war—Sudzha, Kursk region, Russian territory, a boarding school with civilians preparing to evacuate. A Russian aerial bomb. They destroyed the building even though dozens of civilians were there."

"This is how Russia waged war against Chechnya decades ago. They killed Syrians the same way. Russian bombs destroy Ukrainian homes the same way. And even against their own civilians, the Russian army uses similar tactics," he said.

"This is a state devoid of civility. And this is an evil that will not stop on its own. But if we act strongly and decisively, even Russia can be forced to stop. And this must be done to ensure the world is safe from Russian bombs," Zelenskyy said.

The war between Ukraine and Russia is heading towards competing for three years.

According to reports, Moscow has stepped up its air attacks on Ukraine in recent times.

Meanwhile, a Ukrainian military official said North Korean soldiers, who were fighting for Russia, were not seen on the frontlines in Kursk for several weeks.

“The presence of DPRK troops has not been observed for about three weeks, and they were probably forced to withdraw after suffering heavy losses,” a spokesperson for the Ukrainian military’s Special Operations Forces, Colonel Oleksandr Kindratenko, told CNN.

Quoting Ukrainian officials and Western intelligence reports, the American news channel claimed that 12,000 North Korean soldiers had been sent to Russia to fight against Ukraine.

Among them, 4,000 have been killed or injured.

They were deployed in the Kursk region since November to repeal Ukraine's incursion.

Ukraine has recently made advancements in Kursk, according to a battlefield update from the Institute for the Study of War (ISW), a DC-based think-tank, reported CNN.