(Bloomberg) -- A Chinese doctor, Li Wenliang, who was reprimanded by police after warning colleagues about a new respiratory disease emerging in Wuhan, has died after falling ill, according to a person familiar with the matter.

Li had been admitted to a hospital in early January and later confirmed to have the coronavirus, according to a post on his social media account. The exact cause of death wasn’t immediately known.

Li on Dec. 30 posted in a social media group about a SARS-like illness that within weeks would explode into the coronavirus epidemic that has infected more than 25,000 people. Days after his warning, he was reprimanded by police for rumor-mongering online, and then later was given an apology, according to his social media account.

The death was reported earlier by the Global Times, a Chinese state-run media organization, and other Chinese outlets. A person familiar with the situation confirmed Li’s death to Bloomberg.

“We’re very sorry to hear of the loss of any person on the front line,” said Mike Ryan, executive director of the World Health Organization’s Health Emergencies Program, at a press conference in Geneva. “We will mourn his death with our colleagues.”

Read Bloomberg’s breaking-news coverage of the outbreak here.

--With assistance from Adveith Nair.

To contact Bloomberg News staff for this story: Dong Lyu in Beijing at dlyu3@bloomberg.net;Haze Fan in Beijing at hfan40@bloomberg.net

To contact the editors responsible for this story: Drew Armstrong at darmstrong17@bloomberg.net;Rachel Chang at wchang98@bloomberg.net

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