An employee of the Mass Transit Railway (MTR) system holds a 'stop' sign at a station in Hong Kong, China, September 2, 2019.

A patient is wheeled as healthcare staff hold posters and participate in a human chain to protest against the police brutality during the anti extradition bill protests, at Queen Mary Hospital, in Hong Kong, China, September 2, 2019.

Choco Chu, 23, shouts slogan from his rooftop at Sham Shui Po in Hong Kong, China, August 29, 2019.

A riot police holds his shield at a Mass Transit Railway (MTR) station in Hong Kong, China, September 2, 2019.

Students cover their eyes as they protest at Edinburgh Place in Hong Kong, China September 2, 2019.

School students boycott their classes as they take part in a protest in Hong Kong, China September 2, 2019.

School students boycott their classes as they take part in a protest in Hong Kong, China September 2, 2019.

People hold placards as they take part in a general strike at Tamar Park in front of the government buildings in Hong Kong, China September 2, 2019.

People take part in a general strike at Tamar Park in front of the government buildings in Hong Kong, China September 2, 2019.

Students boycott their classes as they take part in a protest against the extradition bill at the Chinese University of Hong Kong, China September 2, 2019. REUTERS/Tyrone Siu

Students boycott their classes as they take part in a protest against the extradition bill at the Chinese University of Hong Kong, China September 2, 2019.

Healthcare staff hold placards to protest against the police brutality during the anti extradition bill protests, at Queen Mary Hospital, in Hong Kong, China, September 2, 2019.

Students boycott their classes as they take part in a protest against the extradition bill at the Chinese University of Hong Kong, China September 2, 2019.

A four-metre-tall statue called 'Lady Liberty Hong Kong' is seen during student protests at the Chinese University of Hong Kong, China September 2, 2019.

People point flashlights during a general strike at Tamar Park in front of the government buildings in Hong Kong, China September 2, 2019.

People take part in a general strike at Tamar Park in front of the government buildings in Hong Kong, China September 2, 2019. Image used for illustrative purpose.

School students boycott their classes as they take part in a protest in Hong Kong, China September 2, 2019.

Students boycott their classes as they take part in a protest against the extradition bill at the Chinese University of Hong Kong, China September 2, 2019.

Riot police wait at a Mass Transit Railway (MTR) station as commuters walk past to catch a subway train, in Hong Kong, China, September 2, 2019.

A healthcare staff holds a placard which reads " Saline water and scissors are not weapons", as other staff members participate in a human chain to protest against the police brutality during the anti extradition bill protests, at Queen Mary Hospital, in Hong Kong, China, September 2, 2019.

A protestor stands in front of the Chinese People's Liberation Army Forces Hong Kong Building during a general strike in Hong Kong, China September 2, 2019.