Hong Kong's leader Carrie Lam has warned that the Chinese military could step in if an uprising for democratic reforms that has rocked the city for months "becomes so bad" but reiterated the government still hopes to resolve the crisis itself.
Lam today urged foreign critics to accept that the four months of protests marked by escalating violence were no longer "a peaceful movement for democracy."
She said seeking Chinese intervention was provided for under Hong Kong's constitution but that she cannot reveal under what circumstances she will do so.
"I still strongly feel that we should find the solutions ourselves. That is also the position of the central government that Hong Kong should tackle the problem on her own but if the situation becomes so bad, then no options could be ruled out if we want Hong Kong to at least have another chance," she told a news conference.
The protests started in June over a now-shelved extradition bill that would have allowed some criminal suspects to be sent to mainland China for trial but have since morphed into a larger anti-government movement.
Protesters fear the bill is an example of Beijing's increasing influence over the former British colony, which was promised a high level of autonomy when it returned to Chinese rule in 1997.
The unrest had pummelled tourism and hurt businesses in the global financial hub, further bruising the city' economy as it grapples with effects of the US-China trade war.
American President Donald Trump on Monday urged Chinese President Xi Jinping to ensure a "humane solution" in Hong Kong.
He warned that any "bad" outcome could hurt trade talks ahead of negotiations in Washington this week.
Hardening her government's stance on the protests last week, Lam invoked a colonial-era emergency law last week to criminalise the wearing of masks at rallies but it fuelled more anger, with continuous daily violence over the long holiday weekend.
Police officers last week fired gunshots while under attack from protesters, wounding two teenagers who were the first victims of police gunfire since the protests started.
Enforcement of the mask ban began Saturday, and Lam said it was too early to call it a failure. Two people have been charged with violating the mask ban so far, which is punishable by up to a year in jail and a fine upon conviction.
City University student Ng Lung-ping, 18, and unemployed woman Choi Yuk-wan, 38, were granted bail at a court on Monday after they were accused of taking part in an unlawful assembly outside Kai Tin Shopping Centre in Lam Tin, which was held at the weekend.
They allegedly used a facial covering that was likely to prevent identification without lawful authority or reasonable excuse in the early hours of Saturday, the day the anti-mask legislation came into force.
Critics fear the emergency law, which gives Lam broad powers to implement any measures she deems necessary, could pave the way for more draconian moves.
Lam said the government would make "careful assessment" before imposing other measures under the law, such as internet controls.
She also pledged to continue dialogue and take steps to address livelihood and economic problems in a policy address due October 16 when the Legislative Council resumes.
Protesters stormed and damaged the legislative building on July 1, requiring repairs.
Lam appealed for peace when the legislative session reopens, warning that further disruptions would set back the approval of bills and impede the city's development.
The city's subway and trains, that carry some 5 million passengers daily, mostly reopened today but will shut early amid fear of more protests. The entire MTR network was shut down Saturday, with limited services the last two days.
Video footage on local media showed masked protesters smashing windows of a train heading to mainland China late Monday as passengers screamed — the first time a train carriage was attacked. Protesters also threw objects on the rail track as the train pulled away.
An MTR spokesman, who identified himself only as Terry, confirmed the incident and said some cross-border services have been suspended today.
Scores of students wore masks in defiance as they returned to school. Some rallied at lunchtime, chanting slogans and holding placards that read "You may take away my mask but not my belief" and "Ideas are bullet-proof."
Schools told to report students
Lam's warning comes as reports emerge of secondary school principals in Hong Kong being asked to tell the Education Bureau how many students boycott class or wear a mask to school.
With a public holiday yesterday, today marks the return to school after a long weekend of citywide protests against the anti-mask law that came into effect on Saturday.
Two secondary school principals confirmed to the South China Morning Post that the bureau had sent a message on Sunday telling them to supply information including the number of students who boycott class, wear a mask to school, and whether students are staging any non-cooperation movements.
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But both principals believed the bureau was just trying to get an accurate idea of students' latest reactions, instead of trying to monitor the internal activities at city schools.
In a WhatsApp message sent by the bureau to secondary school principals, and seen by the Post, officials said head teachers should hand over the information this morning via WhatsApp or phone, and asked them to make a note of students who take "abnormal leave", as well as to record any "special incidents" at school.
These would include students chanting slogans, staging sit-ins, and forming human chains.
The message also said if bureau officers did not receive that information by 11am today, they would call schools for the details.
One source said principals from different school districts had received the message, but believed the main purpose of gathering such information was for the bureau to "better understand the trends" of students' reactions to the new law.
No students' personal data would be handed to the bureau, the source said, and he also thought the bureau would require figures for the rest of the week, with some student groups calling for non-cooperation movements over the next few days.
Last month, just after the school year began, the bureau asked secondary schools to tell it how many students boycotted class, the source said, but because there was a "calmer atmosphere" back then, it did not make it mandatory for schools to supply that information, until now.
The revelations came after the bureau issued a letter to school principals and supervisors on Friday - hours before the ban came into effect - to remind students not to wear a mask inside or outside school, unless for "religious or health reasons".
That was criticised in some quarters as "unnecessary", because schools were not affected by the new law, but in response the bureau said its letter was merely a reminder to students of the new law, and it "had not, and would never, collect names of students who wear a mask to school".
Education sector lawmaker and vice-president of the Professional Teachers' Union Ip Kin-yuen said he believed collecting student numbers was "totally unnecessary", as it would only put more pressure onto schools.
"What does the bureau really want to achieve by collecting such figures?" he said.
"And what if some of the non-cooperation movements happened solely outside school, should these events be reported as well?"
However, Wong Kwan-yu, president of the Hong Kong Federation of Education Workers, said it was a "responsible act" for the bureau to want to have a better understanding of the latest situation inside schools, adding he believed students who wore masks to school might mean they "endorse violence".
He said it was only reasonable for the bureau to get a better idea and act on it, rather than to "simply allow such acts to continue".
In a written reply on Sunday night, the bureau said it had been contacting schools every day since the start of the new school year to understand class boycotts, and whether there were any "special incidents" to provide any help necessary.
The bureau also stressed it did not and would not collect any personal information from schools.
Last month secondary school students held at least two citywide class strikes, and staged non-cooperation movements in and outside school, including forming human chains, singing the protest song Glory to Hong Kong, and chanting slogans. Many students wore masks during those events.
- AP, South China Morning Post