Huge clouds of steam billowed from the streets of Novosibirsk on Wednesday after a pipe carrying boiling water for heating homes burst, marking the second such incident in the Siberian city over the past week.A gush of steam, described as a geyser onsocial media, reached as high as the seventh floor of nearby apartment blocks when the heating pipe burst not far from the center of Novosibirsk, Russia's third-largest city.A defect occurred on a pipeline 700 millimeters in diameter, Novosibirsk's mayor's officesaid on the social network Vkontakte, adding that hot water and heat will be reduced until Wednesday evening.It latersaid 200 homes in the affected area were left without heating as utility services worked to fix the damaged pipe.Utility provider Siberian Generating Companysaidsix hospitals, as well as eight schools and kindergartens, are also in the area affected by the heating outage.Temperatures in Novosibirsk are expected to drop from a frigid minus 20 degrees Celsius on Wednesday to an even more bone-chilling minus 30 C on Thursday.At least five residents were injured by boiling water that flooded city streets, health officialstoldlocal media.Following a similar pipe burst last week, hundreds of Novosibirsk residents reportedly still do not haveheating in their homes.Unprecedented heating outages have been multiplying in Russian cities since the New Year holidays, with freezing temperatures across much of the country compounding the severity of what is quickly growing into a major crisis for the authorities.