A vocal critic of the Chinese authorities' response to the coronavirus pandemic has reportedly been arrested after posting a video purportedly showing a February protest against medical insurance reforms.

Zhang Hai was arrested on Saturday or before, according to a website that supports human rights activities in China.

Thousands of elderly people in Wuhan staged a protest against huge cuts to their medical benefits in February.

Zhang fell out of contact after posting on Twitter a video that apparently shows the rally, according to the website.

Zhang has claimed that the Chinese authorities were responsible for the death of his father, who died from the coronavirus.

He told foreign media outlets that his father's death was due to the authorities hiding information from the public.

Local authorities across the country appear to be on edge, as similar protests are also erupting in other cities.