Hong Kong police fired tear gas and water cannon to disperse anti-government protesters who threw rocks, broke windows and blocked a key road next to a huge pro-democracy rally, near the local headquarters of China's People's Liberation Army (PLA).
The protesters, many dressed all in black and wearing masks, took cover under umbrellas and fled after the demonstrations took a familiar turn into violent clashes with police as they often have over the past three months.
Police fired blue water, used in other countries to help identify offenders, as protesters regrouped 100 yards (metres) away.
They had smashed windows of government offices and tried to break in, shouting obscenities and daubing slogans on shop-fronts. They had also shone lasers at a helicopter hovering overhead.
"A large group of violent protesters are occupying Harcourt Road. They also hurled bricks at police officers. Their acts pose a serious threat to the safety of everyone on site," police said in a statement.
Thousands, young and old, had gathered peacefully at a harbourside park to mark the fifth anniversary of the "Umbrella" pro-democracy movement which gridlocked streets for 79 days in 2014. A band was playing Beatles music as the violence erupted.
The park sits in front of central government offices and the Legislative Council, both of which have come under attack before, sparking violent street battles with police.
"It's a special day for Hong Kong protesters. We will stick together to fight for freedom," said Sam, 33, dressed in black and wearing a mask. "Most people think Hong Kong was dying after five years, but many people are still fighting for Hong Kong."
A series of protests for and against Communist Party rulers in Beijing is planned for the Chinese-ruled city ahead of the 70th anniversary of the People's Republic on Tuesday, including at the consulate of former colonial power Britain.
The Hong Kong building of the Chinese state-owned investment company CITIC, next to the Legislative Council, ran a huge purple LED-lit banner down its front commemorating National Day.
Anti-government protesters have attacked the legislature, Beijing's main Liaison Office, occupied the airport, thrown petrol bombs at police, vandalised metro stations and set street fires.
Police have responded with tear gas, water cannon, rubber bullets and occasional live rounds fired into the air.
The MTR subway system closed entrances to some stations on Saturday to prevent fresh attacks.
LENNON WALLS
"They are not our children," China supporter Yau Mei-kwang said of the frontline activists. "Because at this age, they should be studying, not running to the airport, hitting people, hitting the police, insulting people. That is not right."
A pro-democracy protester who only gave his name as Wong defended the use of violence. "We know that they will not listen if we rally in peace because we are not on the same level."
Protesters had spent the afternoon rebuilding "Lennon Walls" of anti-government graffiti, some of which were torn down by pro-Beijing activists last weekend.
Anti-government protesters are angry about what they see as creeping Chinese interference in Hong Kong, which returned to China in 1997 under a "one country, two systems" formula guaranteeing freedoms that are not enjoyed on the mainland.
China dismisses the accusation and has accused foreign governments, including the United States and Britain, of fanning anti-China sentiment. It has denounced the protests but said it has faith in the Hong Kong government to resolve the crisis without the use of PLA troops based in the territory.
Protesters appealed to Britain two weeks ago to rein in China and ensure it respects the city's freedoms. They plan to do so again on Tuesday.
BROADER MOVEMENT
Britain says it has a legal responsibility to ensure China abides by the 1984 Sino-British Joint Declaration. At the same time, it wants closer trade and investment cooperation with China after it leaves the European Union at the end of October.
Protests were sparked in June by planned legislation, since withdrawn, that would have allowed the extradition of suspected criminals to mainland China. But they have since expanded into a broader pro-democracy movement.
One of the leaders of the protests, the bespectacled Joshua Wong, 22, said on Saturday he would run for local district council elections in November.
"It's time to let Emperor Xi (Chinese President Xi Jinping) be aware that now is our battle," he told reporters. "We stand in solidarity, we stand as one."
Official festivities for National Day have been scaled back, with authorities keen to avoid embarrassing Beijing just as Xi seeks to project an image of national strength and unity.
(Except for the headline, this story has not been edited by NDTV staff and is published from a syndicated feed.)
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