Russia has expressed outrage as it reported that a Ukrainian drone attack killed at least four people in the occupied Luhansk region.

The Moscow-installed regional governor, Leonid Pasechnik, reported on Friday that a student dormitory in Starobilsk was hit. The Kremlin, which has killed thousands in Ukraine since launching its full-scale invasion over four years ago, described it as a “monstrous crime”.

Pasechnik said Ukrainian drones hit a five-storey dormitory belonging to Luhansk Pedagogical University during the overnight attack. The building then collapsed to its second-floor.

About 86 children and teachers were inside when the drone struck, Russian authorities said. At least 35 were injured, three critically, with some trapped under the rubble. The victims were aged between 14 and 18.

“Rescuers continue to pull out the injured children and bodies of the dead, despite a repeated threat of more UAV attacks,” said Yulia Shapovalova, Al Jazeera’s Moscow correspondent.

Luhansk, over which Russia claimed full control in April, is one of four Ukrainian regions occupied or partly occupied by Russian forces.

Both Russia and Ukraine deny targeting civilians in the continuing war, which was sparked by Moscow’s forces launching a cross-border assault in February 2022.

Kremlin spokesman Dmitry Peskov called for those responsible to face justice.

“This is a monstrous crime. An attack on an educational institution where children and young ⁠people are present,” he said, according to Reuters news agency.

Russian Foreign Ministry spokesperson, Maria Zakharova, told state-owned news agency RIA Novosti that the strike was a “deliberate” attack against children.

Ukraine is yet to respond to Russia’s allegations, or the reported attack on the dormitory.

Moscow has launched a criminal investigation. According to Russia’s Investigative Committee, Ukraine used four UAVs to strike the dormitory and other buildings in Starobilsk.

Photos and video released by Russian authorities showed rescue workers carrying one man out of the rubble of severely damaged buildings – one of them ‌appeared to have partially collapsed, with fires still burning.

Yana Lantratova, Russia’s human rights commissioner said they expect international organisations to respond to the attack on a “civilian facility where children study and live”.

Russia’s Defence Ministry said 217 Ukrainian drones were shot down overnight across the country.

Constant attacks by Ukraine have “negatively impacted” Russia’s oil and domestic petrol production, said Shapovalova.

“Analysts say the situation may lead to significant disruptions for Russia’s economy and its ability to carry on with the war with Ukraine.”

The report of the Luhansk attack follows a pledge by Ukrainian President Volodymyr Zelenskyy to respond to Russia’s recent raid on Kyiv which killed 24 people.