Ukrainian soldiers are now using a long-range drone capable of traveling up to 2,000 kilometers (1,242 miles) and carrying a 250-kilogram air bomb, the Unmanned Systems Forces said on Jan. 31. The drone is described as a “unique development” and a potential game changer on the battlefield.

"This refinery is one of the 10 largest oil refineries in Russia in terms of design capacity and is involved in supplying the Russian occupatying army," the General Staff said in a statement.

A Russian drone attack on a residential block killed eight people including three elderly couples in the eastern Ukrainian city of Sumy, prosecutors said on Thursday.

The drone blew out a wall and surrounding windows in the building in Sumy, a major city, just after 1 a.m., the Sumy regional administration said.