Local news outlets claim that authorities burst into 84 homes of people isolating in the Liwan district of Guangzhou city in a bid to find close contacts remaining inside and to disinfect the premises.
The doors were later sealed and new locks installed, the Communist Party newspaper Global Times reported.
The district government apologised for such “oversimplified and violent behaviour”, the paper said.
A team has been set up to investigate and “relevant people” will be severely punished, it added.
China’s leadership has maintained its hard-line “zero-Covid” policy despite the mounting economic costs and disruption to the lives of ordinary citizens.
Residents continue to be subjected to routine testing and quarantines, even while the rest of the world has opened up to living with the disease.
Numerous cases of police and health workers breaking into homes around China in the name of anti-Covid measures have been documented on social media.
In some, doors have been broken down and residents threatened with punishment, even when they tested negative for the virus.
Authorities have demanded keys to lock in residents of apartment buildings where cases have been detected, steel barriers erected to prevent them leaving their compounds and iron bars welded over doors.
