No fewer than nine people were buried in debris after four apartment buildings collapsed Thursday near Wenzhou, an industrial city in eastern China, state television reported.
The people belonged to two families, according to local officials cited by Xinhua news agency. It was unclear from the report what their status was.
The collapse happened around 8 a.m. (0000 GMT) in the township of Baizhangji, in Zhejiang province.
Its cause is under investigation, according to Xinhua.
Eight fire brigades and about 100 firefighters assisted with the rescue operation.
By 1 p.m. (0500 GMT) they had made little progress, Xinhua said.
The scene is quite chaotic, as if the place had been levelled by an earthquake,” a rescuer told Xinhua by telephone. `
“We have to work very carefully because the wreckages of the ruined buildings are joined to homes still standing.”
One of the adjacent homes already had a hole in its outer wall, the rescuer said.
Photos posted by Xinhua on Twitter showed rescue workers using heavy equipment to clean up debris.
Fire trucks were lined up next to the site, and dozens of people were shown looking on.
Thursday is the last day of the Chinese New Year holiday, a period in which millions of people travel to their hometowns and authorities tend to avoid communicating bad news.
Wenzhou is a major manufacturing hub, attracting migrant workers from across the country.
In October, at least 22 people died after four apartment buildings in the city collapsed.
The buildings hosted mostly migrant workers, according to state media reports.
Several buildings have collapsed in recent years in China, where rapid urbanization has been accompanied by often shoddy construction.