Three people were killed as gas pipeline exploded in a residential area on Saturday (March 25) in northern China's Inner Mongolia, state media reported. <br /> <br />State broadcaster CCTV put out amateur footage showing the destroyed buildings, saying that one of the structure collapsed completely in Xiangyang community. <br /> <br />The blast happened at around 2 p.m. (0600 GMT), leaving four people severely injured and 21 with minor injuries, it added. <br /> <br />Rescue operation and investigation are now underway, CCTV reported.