Rescuers try to pull out a survivor Wednesday. [Photo/Weibo]

The center's partners and social NGOs provided donations. "We received about 70,000 yuan in capital donations, food, clothes and daily necessities. Restaurants nearby also brought us food for free," Niu said.

He added that the capital donations had been sent to the Red Cross Society of China, which has donated 500 packages of necessities to residents at the innovation center's temporary shelter.

However, the people sheltered there still urgently need to get their ID cards andc ash, Niu said, adding that "there are also children here who need their books for school".

He estimated that the facility will provide emergency shelter for as long as one month, but he said he did not know where the people staying there will go after that.

Li Hongxia from the Dengzhou chamber of commerce in Shenzhen said that so far, three families from Dengzhou, a small city in Henan province, have reported missing relatives, with one family unable to contact five members.

A hotline set up by the chamber has received dozens of calls regarding missing people. The chamber promised to provide dormitory facilities and help displaced workers find jobs in Shenzhen or in Dengzhou.

According to the list of the missing, 22 are from Henan. Also among the missing are workers from Guizhou, Hunan, Sichuan and Guangdong provinces, the Guangxi Zhuang autonomous region and Chongqing.

KuangChi Science Ltd, a Shenzhen-based high-tech company, also participated in the rescue effort with high-resolution earth observation equipment, which can find survivors by detecting heat sources.