Pro-democracy activists have jammed Hong Kong streets in a march to the United States consulate in a bid to ramp up international pressure on Beijing, but hardcore protesters later clashed with riot police across the city's core.
Millions have demonstrated over the last 14 weeks in the biggest challenge to China's rule since the city's handover from Britain in 1997.
The protests were lit by a now-scrapped plan to allow extraditions to the authoritarian mainland, seen by opponents as the latest move by China to chip away at the international finance hub's unique freedoms.
But after Beijing and city leaders took a hard line the movement snowballed into a broader campaign calling for greater democracy, police accountability and an amnesty for those arrested.
Sunday's protest featured another massive turnout for a movement that has gripped the semi-autonomous territory and plunged it into a political crisis.
Dense crowds of protesters spent hours slowly filing past Washington's consulate in the thick tropical heat. Many waved US flags, some sang the Star Spangled Banner, and others held signs calling on President Donald Trump to "liberate" Hong Kong.
In chants and speeches they called on the US to pressure Beijing to meet their demands and for Congress to pass a recently proposed bill that expresses support for the protest.
"More than 1,000 protesters have been arrested. We can't do anything but come out onto the streets. I feel hopeless," said 30-year-old protester Jenny Chan.
"I think aside from foreign countries, no one can really help us," she added.
In what has become a now familiar pattern, the main daytime rally passed off peacefully.
But as evening set in, riot police chased groups of hardcore protesters who blocked roads, vandalised nearby subway stations and set makeshift barricades on fire.
One fire burned at an entrance to the subway in the corporate district of Central, where a protester also smashed the station's exterior glass.
In the shopping area of Causeway Bay, officers fired tear gas outside another subway station.
Paramedics took away on a stretcher a man who collapsed after inhaling the gas, and police detained suspected protesters inside that station.
Hong Kong is a major international business hub thanks to freedoms unheard of on the mainland under a 50-year deal signed between China and Britain.
But Beijing balks at any criticism from foreign governments over its handling of the city, which it insists is a purely internal issue.
Authorities and state media have portrayed the protests as a separatist movement backed by foreign "black hands", primarily aiming their ire at the US and Britain.
While some American politicians on both sides of the aisle have expressed support for the democratic goals of the protesters, the Trump administration has maintained a more hands-off approach while it fights a trade war with China.
President Trump has called for a peaceful resolution to the political crisis and urged China against escalating with a violent crackdown.
But he has also said it is up to Beijing to handle the protests.
Washington has rejected China's allegations that it is backing the demonstrators and Beijing has shown little evidence to back its claims beyond supportive statements from some politicians.
Timeline of unrest in Hong Kong
The protests show no signs of abating, and the city's unelected pro-Beijing leader Carrie Lam has struck an uncompromising tone for much of the last three months.
On Wednesday,she made a surprise concession, announcing the full withdrawal of the proposed extradition bill which sparked the demonstrations.
Protesters across the spectrum dismissed the gesture as too little, too late, saying their movement would only end once the remainder of their core demands were met.
"Our government continuously takes away our freedoms and that's why people are coming out," said a 30-year-old protester in a wheelchair who gave his surname as Ho. Analysts say it is difficult to predict what Beijing's next move might be.
Under president Xi Jinping, China has become increasingly authoritarian and dissent is being stamped out with renewed ferocity.