The Russian military has launched a “massive strike” overnight against Ukrainian military targets using intermediate-range hypersonic missiles and other systems, including the Oreshnik hypersonic missile system, Iskander ballistic missiles, Kinzhal and Zircon hypersonic cruise missiles, as well as air-, sea- and ground-launched cruise missiles and attack drones.

The operation followed a drone strike by Ukrainian forces on a teacher training college dormitory at Starobelsk College — a facility of Lugansk Pedagogical University — in the town of Starobelsk, Lugansk People’s Republic, on Friday that killed 21 people and injured 42, most of whom were teenage girls.

According to the Russian Defense Ministry, the strike targeted Ukrainian military command and control facilities, air bases, and defense industry enterprises. The ministry stated that no strikes had been planned or carried out against civilian infrastructure.

“The objectives of the strike have been achieved. All designated targets were hit,” it stressed.

A governor in Lugansk declared May 24-25 days of mourning for the victims, describing the incident as “pure evil” and stating that those responsible would face “deserved and inevitable punishment.”

The U.S. Embassy in Kiev had previously warned American citizens of a potential significant air attack within 24 hours.