Residents in Chengdu say they were told to stay inside through a 6.6-magnitude earthquake on Monday that has killed at least 65 people.
Those that ran out say they found the exits shut due to Covid restrictions.
Chengdu, home to 21 million people, is currently under strict lockdown rules.
China has a so-called zero Covid-19 policy, meaning that lockdowns are routinely imposed in communities when cases of the virus are detected.
In some instances, apartment buildings where at least one person has tested positive for Covid have been designated “sealed areas” – where residents are forbidden from setting foot outside their homes whether or not they have the virus.