Ukraine authorities began “criminal proceedings” Monday against Russian soldiers blamed for the missile strike that devastated a nine-story apartment building in Ukraine and killed at least 40 people, one of Moscow’s deadliest attacks on civilians away from battle areas.

At least 25 people remained missing from Saturday’s assault in the central Ukraine city of Dnipro, and rescue teams continued picking through the rubble in hopes of finding survivors, the Ukraine Security Service said. At least 75 were injured, 14 of them children, in a building that was home to about 1,700 people.

Seventy-two apartments were destroyed and 236 were damaged, leaving hundreds of Ukrainians homeless in the dead of winter. The security service said several dozen Russian soldiers were involved, led by Col. Timoshin Oleg Evgenievich, commander of Russia’s 52nd Heavy Bomber Aviation Regiment.