Police in northwest China's Gansu Province on Thursday detained two people in connection with a food poisoning case that left 131 people ill.

Police in Yuzhong County said snack vendors Li Jianlin, 37, and Tie Jianzhong, 34, were detained on Thursday morning. The two, both native to Cuiyao Village, Tianshui City, were suspected of selling problematic niangpi, a wheat snack popular in the region, which led to the poisoning.

They were selling the snack without licenses, police said.

But Li and Yu said they bought the niangpi from another vendor in Lanzhou, capital of Gansu, and they only made the seasoning.

Police are still investigating.

At least 131 people in Yuzhong were reported to have developed symptoms of nausea, vomiting and diarrhea, according to the county's health bureau.

An initial investigation showed that most of the patients, aged from 3 to 71, became ill after eating niangpi sold by Li and Tie.

Police said a specific laboratory report on the food would be released soon.

(Xinhua News Agency May 1, 2009)