China reported its first cluster of Covid-19 cases among workers in a meat processing plant, raising fears among local consumers who have until now mainly worried about the safety of imported foods.

Ten confirmed cases were found in a factory which slaughters 50 million chickens a year in the northeastern city of Harbin and is owned by Thai conglomerate Charoen Pokphand, one of the world's top poultry producers, according to Reuters.

Another 28 workers at the plant and three family members were asymptomatic, officials told a news briefing.

While China repeatedly pointed to imported frozen meat and fish as the source of coronavirus cases last year, it has not reported significant clusters in its own food processing sector.