Li Wenliang died of infection early on Friday, his hospital announced.

China's anti-graft watchdog announced Friday an investigation after the death of a whistleblowing doctor sparked anger over the government's handling of the coronavirus emergency.

The discipline inspection commission said a team would go to Wuhan, the virus-hit city where doctor Li Wenliang died, to "conduct a comprehensive investigation into issues involving Dr. Li Wenliang reported by the masses".

Li, 34, died early Friday, Wuhan Central Hospital said in a post on China's Twitter-like Weibo platform.

The death of the ophthalmologist sparked an outpouring of grief and anger over a worsening crisis that has now killed more than 630 people.

At least 31,000 people have now been infected by a virus in China and cases have been found in over two dozen countries, triggering an international health crisis.

Li was among eight physicians punished by Wuhan police for discussing the emergence of a SARS-like virus on social media in December.

China's supreme court in January criticised Wuhan police for punishing early "rumour mongers," saying the outbreak may not have become so serious "if the public had believed these 'rumours' at the time."