China's food regulator has visited 600 fast food outlets and food distributors over fears out-of-date or rotten meat is being sold for consumption, the watchdog said in a statement.
Big chains like McDonald's, Starbucks and KFC-parent group Yum Brands Inc have already been dragged into the safety scare.
The investigation comes after five people from OSI Group, the US parent of China-based meat-processing factory at the center of the incident, were arrested. Yum has now severed ties with the group.
More top news
A woman who refused to get married as a 'fat bride' tells GMB she shed six stone after a nasty jibe about her weight left her in tears.
A car ended up on a motorway embankment and got stuck in the trees after the driver lost control.
The pristine collection from the 1960s and 1970s could net owner Doug Carpenter a packet if they sell at auction today.