At least eight people have been killed and 12 were injured after a section of a nine-storey apartment building in southern Russia collapsed following a natural gas explosion, officials said Tuesday. Anzhelika Barinova of Russia's Emergency Situations Ministry says two others are still missing after Monday's explosion in Astrakhan, 1,300 kilometers (800 miles) southeast of Moscow. Prime Minister Vladimir Putin, who is running to reclaim the presidency in Sunday's vote, rushed to the explosion site Tuesday and quickly ordered the local authorities to immediately find new apartments for all the residents of other sections of the building, replying to their fears that the entire structure could collapse.