Hundreds of rescue workers were searching for survivors after a two-story restaurant collapsed in northern China, killing 29 people, state media reported on Saturday.

Rescue workers in orange overalls, wearing hardhats and masks, were deployed to the site in Shanxi province's Xiangfen county, roughly 630 kilometers (400 miles) southwest of Beijing

The Ministry of Emergency Management said 28 people were injured, seven of them seriously, when the building suddenly crumbled on Saturday.

A total of 57 people were brought out alive, the ministry said.

Read more: Several killed after roof collapse in Shanghai Mercedes-Benz dealership

Cause of collapse unknown

The restaurant reportedly collapsed at around 9:40 a.m. local time (1:40 a.m GMT).

The cause of the tragedy was not immediately apparent.

Video footage posted on social media by state broadcaster China Central Television showed workers lifting heavy chunks of concrete. On at least one occasion, the remaining parts of the frame of the building shook but ultimately stayed upright.

jsi/dj (AP, AFP)