At least four people have lost their lives in a gas explosion in a multi-storey residential building in the Russian city of Nizhny Tagil in the Urals. Fifteen people were rescued from the rubble, some with serious injuries, the Ministry of Civil Defence for the Sverdlovsk region said on Friday. Two entrances to the building reportedly collapsed completely. More than 500 rescue workers, equipped with heavy machinery, were deployed in the city, which is over 1,300 kilometres from Moscow. In Russia and other former Soviet republics, explosions occur repeatedly of gas pipelines in residential buil…