Lei Lei joined in with the criticism, calling Fang a “Chinese traitor”. In the diary, Fang describes the difficulties of life in quarantine, as well as the spread of the disease and how it wreaked havoc, taking lives and breaking-up families and homes.

“She wrote a diary which has become a tool used by foreigners to attack China,” Lei said, according to a translation by Radio Free Asia, in a video on Chinese social media.

He also called on martial artists to “use their fists for justice” and “punish” Fang.

But now the outspoken Xu has waded into the row.

“Fang Fang is a petite woman of fifty-something [actually 64]; she’s not very strong,” Xu said in his own video, also translated by Radio Free Asia. “I've read [Wuhan Diary]. It's mostly full of praise and encouragement. There's just a small amount of criticism and complaint, and that is all true and realistic.

“It truly never occurred to me that so many people would start abusing her,” he added. “Let's face it, the martial arts world is full of stupid [expletive], but for you, Lei Lei, to call on Wuhan martial artists to go and attack a woman in her fifties for writing something ... have you no shame?”

Xu’s emphatic destruction of Lei Lei in April 2017 set him on his mission of exposing what he deems “fake” kung fu, by challenging traditional martial artists to fights.

“It ushered in a new era, and meant that there wasn't a member of the martial arts world willing to stand up for their country,” Lei Lei added of his embarrassing defeat.

“Now, I am calling on the Wuhan martial arts community. Fang Fang hasn't left China yet, and she hasn't left Wuhan, so you should denounce Fang Fang. Please use your fists for justice and punish this Chinese traitor.”