Rescuers pulled the seventh survivor from a collapsed residential building in Changsha, central China's Hunan Province on Sunday, more than 50 hours after the disaster happened. Sixteen people are still trapped in the rubble of the eight-story building, and another 39 people are missing following the disaster. More than 1,700 firefighters, police officers and emergency response personnel are involved in the rescue operation running day and night. Firefighters are using small-sized dismantling equipment to open a life channel in the rubble to provide nutrition and drinkable liquid for the trapped people. They are also using sniffer dogs, life detectors, cranes, power generators, fire engines and other equipment to search and rescue survivors from the debris. The local police have detained nine suspects for investigation.