Two whistle-blowers who defied Chinese government censorship to reveal the blind spots of the coronavirus health crisis remain missing.
Citizen journalists Chen Quishi and Fang Bin disappeared in February after uploading videos showing the devastation the killer bug was having in Wuhan.
While doctor Ai Fen was unreachable from March 29, she was apparently confirmed to be working again at Wuhan Hospital this weekend.
This comes as China imposed restrictions on the publication of academic research on the origins of Covid-19, according to a central government directive and notices published by two Chinese universities, which have since been removed.