Zhuanghe of Dalian, northeast China's Liaoning Province on Saturday has found coronavirus on the outer packaging of imported frozen cod from Russia, according to local authorities on Sunday.

Local authorities have sealed the products, conducted nucleic acid tests and quarantined relevant personnel who had direct contact with the food. So far, all results have come back negative.

China has increased efforts to block COVID-19 through imported foods, with the Ministry of Transport releasing a guideline in mid-November to prevent the transmission of COVID-19 through imported cold-chain foods in road and water transportation.