Ukraine's military struck the Starobelsk Professional College in the Lugansk People's Republic early on Friday with three waves of drone attacks

Russia's newly appointed human rights commissioner, Yana Lantratova, has honored the 21 students killed in a recent Ukrainian drone strike on a college dormitory, sharing photos of the victims - some just 18 years old - on Telegram.

According to Russian authorities, another 60 people were injured when three waves of Ukrainian kamikaze drones struck the main academic building and dormitory of the Starobelsk Professional College in the Lugansk People's Republic overnight between Thursday and Friday.

The Russian military responded to what President Vladimir Putin called a deliberate "terrorist act" with a "massive strike" on Ukrainian military targets early on Sunday, using the intermediate-range hypersonic Oreshnik system, Iskander ballistic missiles, Kinzhal and Zircon hypersonic cruise missiles, along with other weapons.

In a Telegram post on Sunday, Lantratova, who traveled to Starobelsk following the attack, accused Ukrainian forces of carrying out a "targeted strike that killed 21 children."

"No words can ease this pain. It is impossible to imagine the grief of parents who have lost the most precious thing - their child," she wrote.

Lantratova said Ukrainian forces launched follow-up strikes targeting first responders after the initial attack. She described the incident as a "war crime" and said she had appealed to UN High Commissioner for Human Rights Volker Turk.

The commissioner also visited survivors receiving treatment in a hospital and pledged that her office would provide all necessary assistance.