Rescuers pulled a pair of survivors from a collapsed building in central China on Sunday, state media reported, two days into a search-and-rescue operation for dozens feared missing.
The building in Changsha city, Hunan province -- which housed a hotel, apartments and a cinema -- caved in Friday afternoon, leaving a gaping hole in the dense streetscape.
City officials on Saturday said five survivors had been pulled out of the structure. There are now 16 people believed to remain trapped, according to authorities, while no contact has been made with nearly 40 others.
More than 50 hours into the rescue effort, a seventh person was rescued Sunday evening, state broadcaster CCTV reported, after rescuers "detected signs of life" earlier that afternoon.
"When she was discovered, she was in relatively good condition. Her vital signs were quite stable and she could hold a normal conversation with rescuers outside," a CCTV reporter on the scene said, adding the woman had been separated from rescuers by a wall one meter thick.
CCTV showed footage of an ambulance driving the survivor to hospital, while rescuers worked with a digger in the background.
Another survivor was pulled from the rubble earlier Sunday, as CCTV broadcast images of firefighters hauling a person covered in dust onto a gurney.
Changsha police said nine people -- including the building's owner and a team of safety inspectors -- were detained Sunday in connection with the accident. They alleged that surveyors had falsified a safety audit of the building.
No cause for the disaster has yet been given by authorities.
Changsha's mayor earlier vowed to "spare no effort" in their search for the people still trapped.
"We will seize the golden 72 hours for rescue and try our best to search for the trapped people," mayor Zheng Jianxin said in a news briefing Saturday.
He added that more than 700 first responders had been dispatched to the scene.
State media showed firefighters -- backed by a digger -- cutting through a morass of metal and sheets of concrete, while rescuers shouted into the tower of debris to communicate with any survivors.
A crowd gathered as chains of rescuers removed pieces of brick by hand, allowing experts a deeper look into the wreckage.
President Xi Jinping on Saturday called for a search "at all cost" and ordered a thorough investigation into the cause of the collapse, state media reported.
A top Communist Party official was also dispatched to the scene -- an indication of the severity of the disaster.
China's minister of emergency management Huang Ming urged officials to "thoroughly eliminate all kinds of hidden safety risks" in a Saturday meeting.
Building collapses are not uncommon in China, due to weak safety and construction standards as well as corruption among officials tasked with enforcement.
In January, an explosion triggered by a suspected gas leak brought down a building in the city of Chongqing, killing at least 16 people.
