Local authorities in Shanghai have promised a zero-tolerance approach to breaches of food safety laws after six managers from the company at the center of the expired meat scandal were arrested.

The six work for Shanghai Husi Food Co, which supplied leading fast-food chains, including McDonald's and KFC, with expired meat mixed with fresh meat.

Bai Shaokang, Shanghai's deputy mayor and police chief, said Shanghai will impose strict measures because food safety is essential for the health of residents.

"We have zero tolerance for food and drug safety incidents," he said. "If it is a crime, we will abide strictly by the law and investigate the matter. We will never allow such crimes to go unchecked."

Shanghai Husi is a subsidiary of Chicago-based food company OSI Group. Last month, a TV station reported that Husi was supplying expired meat and deliberately misleading quality inspectors from McDonald's.

In the past, food safety scares have initially been investigated by the Shanghai Municipal Food and Drug Administration. Only when it is established that a crime has been committed is a case handed over to the city's public security authorities.

But Bai said the bureau has investigated the Husi case from the start because of the level of concern about the allegations.

He said it was important for administrative and criminal investigation departments to work together.

"Only with such close cooperation can we ensure a firm hand against food and drug safety crimes," he added.

Guo Zhun, director of the food safety department of the Nature's Friend Ecological Protection Association, a local NGO, urged employees of food companies to help ensure that the food production process is open and transparent.

"There are several ways to avoid such cases happening again," he said. "They include having the companies issue guarantees, making the production and logistics process open and transparent and offering employees rewards for reporting problems.

"But when we visit food and catering companies, very few of them accept our advice. Some even tell us that every food company has a skeleton in the closet."

The Shanghai Municipal Food and Drug Administration has also encouraged company employees to report food safety problems.

In March, the Public Security Bureau set up a food and drug investigation division.

shijing@chinadaily.com.cn