Explosion kills four, injures 20 in Russian city (VIDEO, PHOTOS)

Rescue crews are at the scene of a household gas explosion which caused a building to partially collapse in Nizhny Tagil

Four people, including two children, have died after a gas explosion caused a residential building to partially collapse in the city of Nizhny Tagil in Russia's Urals, the Emergencies Ministry (EMERCOM) said on Friday. The blast destroyed two sections of a five-story apartment