A Ukrainian drone attack launched overnight succeeded in destroying an ammunition depot in the western Russian region of Tver, a source from Ukraine’s Security Service (SBU) told CNN on Wednesday.

A large-scale Ukrainian drone attack on Russia triggered an earthquake-sized blast at a major arsenal in the Tver region on Wednesday, forcing the evacuation of a nearby town, war bloggers and some media reported.

Russia said it was working to repel a Ukrainian drone attack on Toropets, where there's a major military depot, as explosions lit up the night.