Taiyuan, Apr 30 (Reporter) Seventeen people were injured in a residential complex explosion on Wednesday afternoon in Taiyuan, capital of north China's Shanxi Province, with four in critical condition and three discharged after treatment, according to local authorities. The blast occurred in the Beiying neighborhood of Xiaodian District at around 1 p.m. As of 3 p.m., the fire triggered by the blast had been extinguished. Rescue teams are conducting door-to-door safety checks in the affected building, and an investigation into the cause of the blast is underway...////...