The prominent democracy activist is the highest profile figure to be arrested so far under China's new security law.
Chinese-U.S. relations have sunk to their lowest level in decades amid a mounting array of conflicts.
Cases of COVID-19 have been surging for more than a week after trending down for more than six weeks.
Stay up to date as we cover the ongoing coronavirus pandemic and its effects across the world.
China, where the virus first appeared late last year, reported 49 new coronavirus cases on Monday, 36 of them in Beijing.
Such a move has long been under consideration but was hastened by months of anti-government protests last year.
Construction crews worked around the clock to build the 1,000-bed hospital in Wuhan, the central city where the outbreak was first detected in December.
A man who traveled to the Philippines from Wuhan died on Saturday, the Philippines Department of Health confirmed.
The virus’ rapid spread in two months prompted the World Health Organization to declare it a global emergency.
On the eve of the Lunar New Year, transportation was shut down in at least 10 cities with a total of about 33 million people as China fights the coronavirus.