Hong Kong police fired water cannon and tear gas Sunday as crowds held an illegal march, with hardcore protesters throwing petrol bombs and trashing businesses to cap a week of anger after recent attacks on pro-democracy demonstrators.

Thousands joined the unsanctioned rally in Hong Kong regardless
Thousands joined the unsanctioned rally in Hong Kong regardless AFP / Dale DE LA REY

Authorities had forbidden the rally in Tsim Sha Tsui, a densely-packed shopping district filled with luxury boutiques and hotels, citing public safety and previous violence from hardcore protesters.

Tensions were already running high before the march was banned
Tensions were already running high before the march was banned AFP / Ed JONES

But tens of thousands nevertheless joined the unsanctioned demo, showing the movement can still keep pressure on the city's pro-Beijing leaders after nearly five months of protests and political unrest.

In a familiar pattern, the huge rally began peacefully.

Protesters have labelled the attacks 'white terror'
Protesters have labelled the attacks 'white terror' AFP / Philip FONG

But it soon descended into chaos as smaller groups of protesters hurled petrol bombs at police, subway entrances and at Chinese mainland bank branches, and vandalised multiple shops.

Hong Kong has been battered by 20 weeks of pro-democracy protests which have seen millions peacefully take to the streets
Hong Kong has been battered by 20 weeks of pro-democracy protests which have seen millions peacefully take to the streets AFP / Dale DE LA REY

Police responded with volleys of tear gas and rubber bullets, and baton charges.

Throughout the afternoon, a water cannon truck chased protesters down Nathan Road, one of the city's busiest shopping thoroughfares, leaving it streaked with blue dye.

On Saturday night hundreds of mostly masked protesters held a prayer vigil in the commercial district
On Saturday night hundreds of mostly masked protesters held a prayer vigil in the commercial district AFP / Ed JONES

The dye in the water, used to identify protesters, also contains a painful pepper solution.

Thousands of people marched through Mong Kok in Hong Kong in defiance of a police ban on the gathering
Thousands of people marched through Mong Kok in Hong Kong in defiance of a police ban on the gathering AFP / Philip FONG

The entrance to the city's largest mosque was bathed in blue when the water cannon blasted a handful of people outside the building. Police said hitting the mosque was an accident.

Protesters react after police fired tear gas in the Tsim Sha Tsui district of Hong Kong
Protesters react after police fired tear gas in the Tsim Sha Tsui district of Hong Kong AFP / Dale DE LA REY

As the protesters fled, frontliners stayed behind to slow the advance of riot police, setting fire to makeshift barricades. Clashes went on deep into the night.

A Xiaomi and a Best Mart store -- both mainland Chinese businesses -- were set alight.

A protester in a Guy Fawkes mask takes part in a pro-democracy march in Hong Kong
A protester in a Guy Fawkes mask takes part in a pro-democracy march in Hong Kong AFP / Philip FONG

Activists attacked

Tensions were running high after the leader of the group organising the weekend rally, Jimmy Sham, was hospitalised after being attacked by unknown assailants wielding hammers earlier in the week.

AFPTV / Vivian LIN, Celia CAZALE, Yan ZHAO

Then late Saturday, a man handing out pro-democracy flyers was stabbed in the neck and stomach, reportedly by an assailant who shouted pro-Beijing slogans.

Many on Sunday's march said they wanted to show they were unbowed by the attacks and moves by authorities to ban public gatherings.

Hong Kong police fired repeated volleys of tear gas, rubber bullets and baton charges
Hong Kong police fired repeated volleys of tear gas, rubber bullets and baton charges AFP / Ed JONES

"The more they suppress, the more we resist," a 69-year-old demonstrator, who gave her surname as Yeung, told AFP. "Can police arrest us all, tens of thousands of people?"

The rally soon descended into chaos
The rally soon descended into chaos AFP / Ed JONES

Philip Tsoi, a self-described frontline protester, said they needed to keep getting numbers out even though many hardcore activists like him had been "arrested or wounded" in recent weeks.

"What I want is a truly democratic government whose leader is elected by Hong Kong people instead of selected by a Communist regime," he told AFP.

Hong Kong has been battered by 20 weeks of protests and with no political solution in sight, clashes have intensified each month
Hong Kong has been battered by 20 weeks of protests and with no political solution in sight, clashes have intensified each month AFP / Philip FONG

Vigilante violence has mounted on both sides of the ideological divide.

In recent weeks pro-democracy supporters have badly beaten people who vocally disagree with them -- although those fights tend to be spontaneous outbursts of mob anger during protests.

In contrast, pro-democracy figures have been attacked in a noticeably more targeted way, with at least eight prominent government critics, including politicians, beaten by unknown assailants since mid-August.

Protesters have labelled the attacks "white terror" and accused the city's shadowy organised crime groups of forming an alliance with Beijing supporters.

Beijing has denounced the protests as a foreign-backed plot and condemned attacks on those voicing support for China.

But it has remained largely silent on the attacks carried out against pro-democracy figures.

Months of unrest

Hong Kong has now been battered by 20 weeks of protests and with no political solution in sight, clashes have intensified each month.

Hardliners have embraced widespread vandalism, while riot police are quick to respond with tear gas, rubber bullets and, more recently, live rounds.

The rallies were triggered by a now-abandoned plan to allow extraditions to the authoritarian mainland, but have morphed into wider calls for democracy and police accountability.

Protesters are demanding an independent inquiry into the police, an amnesty for those arrested and fully free elections, all of which have been rejected by Beijing and Hong Kong's unelected leader Carrie Lam.

Earlier this month, Lam invoked a colonial-era emergency law to ban face masks.

The decision set off a new wave of protests and vandalism that shut down much of the city's transport network.

In the last fortnight, the clashes have become less intense, with the city's subway closing each night at 10:00 pm.

But protests have continued, with many defying the mask ban during "flashmob" rallies.

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