The ranks of Hong Kong democracy protesters who have paralysed parts of the city swelled into their tens of thousands Monday, digging in for another night of confrontation with police in their campaign for free elections.
In the worst unrest since the former British colony was handed back to China in 1997, demonstrators fought hours of running battles with police Sunday night, choking on clouds of tear gas as officers attempted to suppress the crowds.
Riot police retreated Monday, handing demonstrators both a major morale boost and control of three major thoroughfares on the key financial hub's main island and across the harbour.
But protesters defied government calls to go home and instead readied themselves to counter any new attempt by police to retake the streets.
Pro-democracy groups are locked in a struggle with the city's authorities over China's refusal to grant unfettered democracy, in one of the most significant challenges to Beijing's authority since the bloody Tiananmen protests of 1989.
Public anger over rampant inequality and Beijing's political interference is at its highest in years in a city once renowned for its stability.
Last month China said Hong Kongers could elect their next leader in 2017 but only candidates who had been vetted would be allowed to stand -- a decision critics branded a "fake democracy".
At the largest protest site in Admiralty district, where many international businesses are based, crowds swelled to some 20,000 people by the afternoon, AFP reporters estimated, taking over nearly a kilometre of highway.
Smaller protests in their low thousands blocked key thoroughfares throughout the day in Mongkok and Causeway Bay, two densely packed shopping districts.
"I'm staying until the end, until we get what we want to get, which is true democracy," 18-year-old high school student Michael Wan told AFP, surrounded by thousands of fellow supporters sheltering under umbrellas from the hot sun.
Underlining their assertive stance, some 1,000 masked protesters gathered outside a police station where senior officers held a press conference defending their liberal use of tear gas against crowds on Sunday night.
Tear gas used '87 times'
Assistant Commissioner Cheung Tak-keung said tear gas was used "87 times" at nine different locations.
"Force is used in a situation when we have no other alternatives," he said, adding officers were compelled to deploy the gas when "police cordon lines were heavily charged by some protesters".
However, the Hong Kong Bar Association condemned "excessive and disproportionate use of force" against crowds which it said were clearly predominantly peaceful.
Demonstrators are calling on the city's leader Leung Chun-ying to resign and for Beijing to drop its demand that candidates standing in the next leadership election be vetted by a loyalist committee.
Analysts said it was difficult to predict what might happen next, with the protesters pitted against a Beijing leadership that brooks no dissent on the mainland.
"The difficulty is that there seems to be no going back for both sides," said Surya Deva, a law professor at the City University of Hong Kong. "Which side will blink first is difficult to say, but I think protestors will prevail in the long run."
Students boycotted classes in the past week, and spearheaded the storming of the government's headquarters on the weekend, a move that prompted pro-democracy group Occupy Central to bring forward a mass civil disobedience campaign due to start on October 1.
Reiterating China's hardline stance, foreign ministry spokeswoman Hua Chunying said Beijing opposed "illegal actions that undermine the rule of law and social security".
Hong Kong's leader Leung Chun-ying also dismissed rumours circulating on social media that he planned to call in the Chinese military, which stations a garrison in the city.
"There is absolutely no proof of this," he said.
The ongoing protests forced the closure of many schools and businesses and caused widespread disruption to commuters.
The city's stock exchange opened as usual, but ended the session down 1.90 percent as investors fretted about the impact the ongoing disruption could have on a key regional market.
City authorities also said an annual public fireworks show planned for the October 1 National Day holiday would be cancelled.
Police said 41 people have been injured, including 12 officers in the past few days, and 78 arrests made for offences ranging from forcible entry into government premises, unlawful assembly, disorderly conduct in public place and assaulting public officers.
Britain handed Hong Kong back to China in 1997 under a "one country, two systems" deal that guarantees liberties not seen on the mainland, including freedom of speech and the right to protest.
But tensions have been building in the southern Chinese city over fears that these freedoms are being eroded, as well as perceived political interference from Beijing.
Britain voiced concern Monday about the escalating protests and called for an upcoming consultation process to produce a "meaningful advance for democracy" in the former colony.