On Oct. 23, 396 people fell ill after a wedding banquet in a restaurant named Qinheyuan in Chongyang town.

China's food safety watchdog has ordered health authorities to investigate the food poisoning of almost 400 people at a wedding in Sichuan Province at the weekend.

In the second major food poisoning case in the province this month, 396 people fell ill after a wedding banquet in a restaurant named Qinheyuan on Oct. 23 in Chongyang town, 40km from the provincial capital, Chengdu.

Some 123 people were taken to three local hospitals, and by Wednesday evening 325 had recovered and none of them were in a life-threatening condition, according to Sichuan provincial health department.

The State Food and Drug Administration (SFDA) Wednesday published a circular on its website ordering the department to investigate the restaurant's operations and its licence conditions.

Laboratory tests taken by Chengdu disease control and prevention center found the source of the poisoning was undercooked soft-shelled turtles and crabs served at the banquet, the department said in a statement to Xinhua Wednesday.

The SFDA also asked the provincial health department to provide all necessary medical treatment for the poisoned people.