Chinese police have broken a crime ring that passed off over €1m in rat and small mammal meat as mutton.

Authorities have arrested 904 suspects since the end of January for selling and producing fake or tainted meat products.

Police discovered one suspect had used additives to spice up and sell rat, fox, and mink meat at markets in Shanghai and Jiangsu province.

Police arrested 63 suspects connected to the crime ring in a case valued at more than €1.2m in sales since 2009.

Despite persistent efforts by police authorities, food safety crimes are still prominent and new situations are emerging with new characteristics.

Police confiscated over 20,000 tonnes of fake or inferior meat products after breaking up illegal food plants during the nationwide operation.

Food safety and environmental pollution are chronic problems in China.

Public anxiety over cases of fake or toxic food often spreads quickly.

In April, many consumers lost their appetite for poultry as an outbreak of the H7N9 bird flu virus spread in China.

Sales dropped by 80% in eastern China, where the bird flu has been most prevalent, although experts stress that cooked chicken is perfectly safe.

In March, more than 16,000 rotting pigs were found floating in one of Shanghai's main water sources, triggering a public outcry.

Over-crowding at pig farms was likely behind the die-off and their disposal in the Huangpu river.

The public security ministry said police had confiscated more than 15 tonnes of tainted pork in Anhui province.

As much as 60 tonnes of tainted pork had been sold in Anhui and Fujian provinces since mid-2012.

But it was the rodent meat in particular that people could not stomach, with internet users turning to the popular microblogging site Sina Weibo to vent their outrage.

"Rats? How disgusting. Everything we eat is poison," one user wrote.