BEIJING - China's food safety watchdog has called for local authorities to be on the lookout for smuggled frozen meat after a large amount of smuggled meat, some of which have been frozen for four to five years, was seized by customs.

Meat processors, storage businesses and catering companies should refrain from buying or selling meat with unidentified origins, the China Food and Drug Administration (CFDA) said in a statement published on its website Sunday.

Enterprises should notify the authorities if they have handled such meat since July 2014, it said, adding they must not fabricate or tamper with records.

According to the statement, all the seized frozen meat, including pork, beef and chicken wings, has been destroyed. The General Administration of Customs and the Ministry of Public Security will continue to investigate the illegal meat.

Around 800 tonnes of frozen meat worth about 10 million yuan (1.61 million US dollars) was seized in Hunan Province in June. A total of 20 people were detained.

The CFDA also urged media outlets to objectively report food safety issues. Earlier this week, a science journalist voiced his doubt about the authenticity of the frozen meat news, saying preserving the meat for years seems unlikely.

Experts say smuggled meat products usually are not inspected and contain large amounts of bacteria and blood.