Hundreds of Hong Kong medical workers walked off their jobs on Monday, demanding the city close its border with China to reduce the coronavirus spreading - with frontline staff threatening to follow in the coming days.
The financial hub has 15 confirmed cases of the disease, many of them brought over from the Chinese mainland where the epidemic began and has so far killed more than 360 people.
The action by non-essential medical staff comes as the city's pro-Beijing leadership resists completely sealing the border.
Authorities have argued that doing so would be discriminatory, economically damaging and go against advice from the World Health Organization.
Instead, the city government has closed down some crossings and says arrivals from the mainland have dropped significantly.
But there is growing public anger in a city that maintains a deep historical mistrust of the mainland after the 2003 SARS outbreak - which was initially covered up by Beijing - killed nearly 300 Hong Kongers.
Thousands of members of a newly formed medical worker union voted to strike on Saturday unless their demand for the border to be closed was met, with the first group downing tools on Monday.
The first strikers are "non-essential" staff but the union has said frontline workers, including doctors and nurses, will walk out on Tuesday if their demands are not met.
Staff gathered outside hospitals across the city on Monday morning, handing white ribbons to colleagues encouraging them to join the strike action.
"If there is no full border closure, there won't be enough manpower, protective equipment, or isolation rooms, to combat the outbreak," Winnie Yu, chairwoman of the 9,000 member Hospital Authority Employees Alliance, told reporters.
Hong Kong's government criticised the industrial action, calling on workers to "reconsider their decision, continue to safeguard Hong Kong with their professionalism and together win the battle against the disease".
Follow Emirates 24|7 on Google News.