Massive rains over the weekend triggered flash flooding in southwestern China that trapped a group of hikers inside a canyon, killing 15, state media said Monday. Four people from the group were still missing, the official Xinhua News Agency said. Rescuers were continuing to search for them after reaching 16 who survived the flood in Tanzhangxia Canyon near Chongqing, Xinhua said, citing a statement from the municipal government. The rescuers recovered 15 bodies, it said.