At least five people have been killed and four others injured in a gas explosion in a residential building in southern Russia. The blast occurred early in the morning in the city of Cherkessk in the Karachay-Cherkessia region, which borders Georgia, about 1300 kilometres south of the capital Moscow. The explosion partially destroyed two upper stories of a five-storey residential building, emergency officials said. “It was a loud bang. And then I just couldn’t understand, everything started falling from the ceiling onto my face, glass too. I covered myself with my hands. My husband was in the n…