Beijing, Dec 30: Three people were killed and 11 injured when an explosion ripped through a highrise apartment building in North-East Chinese city of Changchun. The blast occurred on the 13th floor of a high-rise apartment building last afternoon in Changchun, capital of Jilin province, a media report said today. The injured were sent to the local hospital for emergency treatment, the 'China Daily' reported. Initial investigations have concluded that a gas leak was to blame for the blast, but local police said they had not ruled out criminal intent. Bureau Report