Hong Kong (CNN) – Zhang Zhan،, a citizen journalist imprisoned for reporting on the initial COVID-19 outbreak in WuhanChina, in early 2020, urgently needs medical care, according to Human Rights Watch.

The US-based human rights organization has called on Beijing authorities to release former lawyer Zhang, who was arrested in May 2020 and sentenced in December to four years in prison for “provoking quarrels and seeking trouble”. It is a charge commonly used by the Chinese government to target dissidents and human rights activists.

The 38-year-old has undergone several hunger strikes since her arrest and brief hospitalization, but was sent back to prison despite her deteriorating health.

Zhang’s mother, who had a video call with her in October, said her daughter could not lift her head due to lack of strength – she is 1.78m tall – but now weighs around 40kg and needs urgent medical treatment.

“The Chinese government should be held accountable for allowing another peaceful critic to become seriously ill while unjustly imprisoned,” said Yaqiu Wang, senior China researcher at Human Rights Watch. “Governments should demand the immediate release of Chang Chan to prevent an already tragic situation from turning tragic.”

In the early months of the epidemic, Zhang traveled about 600 kilometers from Shanghai to Wuhan to report the spread of the virus and subsequent attempts to contain it, just as authorities began to control Chinese state and private media.

For more than three months, he has documented fragments of closed life in Wuhan and the harsh reality its residents face, from overcrowded hospitals to empty shops. He posted his notes, photos and videos on Wechat, Twitter and YouTube, the latter two of which are banned in China.

A poster calling for the release of Zhang Zhan is on a car in Pasadena, California, November 15, 2020.

Her publications stopped abruptly in mid-May, and it was later revealed that the police had detained her and returned her to Shanghai.

Amnesty International claims, during a previous hunger strike, that she was handcuffed and forcibly fed, a treatment that, according to the group, amounted to torture.

The Chinese Foreign Ministry has not previously responded to CNN about allegations that Zhang was mistreated while in detention.

In a lengthy statement issued in July 2020, the Foreign Ministry denied the Chinese government’s crackdown on journalists who “exercised their right to freedom of expression online” during the pandemic.

“In China, no one is punished or punished simply for being suspended,” the statement said. “The Chinese government has always carried out its response to COVID-19 in an open and transparent manner, and has achieved widely recognized achievements.”

Zhang was one of several freelance reporters who were arrested or disappeared during the onset of the epidemic, when Chinese authorities cracked down on coverage of the virus and propaganda media raced to portray Beijing’s response as effective and timely.

China has the largest number of imprisoned journalists in the world, according to Reporters Without Borders (RSF), and strictly controls the domestic press while banning most foreign media through the Great Firewall, its vast organ of online censorship and surveillance.

In 2020, China expelled journalists from The New York Times, The Washington Post and The Wall Street Journal, in an unprecedented move against the foreign press. Beijing said the move, which came amid a flurry of critical reports about China’s initial response to the coronavirus, was a reaction to Washington’s recent restrictions on how Chinese state media operate in the United States.

Additional reporting by James Griffiths.