Largely peaceful rally descended into chaos after small group of protesters grabbed a Chinese flag and tried to burn it.

Riot police in Hong Kong broke up a rally in support of China’s Uighurs on Sunday – with one officer drawing a pistol – after the initially peaceful protest descended into chaos when a small group of protesters removed a Chinese flag from a nearby government building and tried to burn it.

Organisers stopped the flag being burned, but riot police swooped in with pepper spray, sparking anger from the crowd who threw water bottles.

One officer drew his gun and pointed it at the crowd, but did not fire. At least two protesters were arrested.

Several hundred people joined the rally, with some holding signs emblazoned with the blue and white flag of the independence movement in China’s northwestern territory of Xinjiang.

China has faced international condemnation for detaining an estimated one million Uighurs and other mostly Muslim ethnic minorities in what it calls vocational training centres, but critics say are internment camps.

The emergence of a huge surveillance and prison system that now blankets much of Xinjiang has been watched closely in Hong Kong, which has been convulsed by six months of huge and sometimes violent protests against Beijing’s rule.

Pro-Uighur chants and flags have become commonplace in Hong Kong’s marches, but Sunday’s rally was the first to be specifically dedicated to Uighurs.

The crowd gathered in a square close to the city’s harbourfront listening to speeches warning that the Chinese Communist Party’s crackdown in Xinjiang could one day be replicated in Hong Kong.

“We shall not forget those who share a common goal with us, our struggle for freedom and democracy and the rage against the Chinese Communist Party,” one speaker shouted through a loudspeaker to cheers.

‘Control Freaks’

Many of those attending were waving the flag of “East Turkestan”, the term many Uighur separatists use for Xinjiang, which has a white crescent moon on a blue background.

A man holds a flag during a rally to show support for Uighurs and their fight for human rights in Hong Kong.The characters read “Liberate Hong Kong. Revolution of our times.” [Lee Jin-man/AP Photo]

Others wore blue face masks displaying the East Turkestan flag. People also carried flags for Tibet – another restless region of China – and the self-ruled island of Taiwan that China claims as its own.

China runs Hong Kong on a “one country, two systems” model which allows the city key freedoms that are denied people on the authoritarian mainland.

The framework will end in 2047, 50 years after the handover.

Many people in Hong Kong fear an increasingly assertive China is already eroding those freedoms, especially since Xi Jinping became president.

Many at Sunday’s rally said they felt a mainland-style government was around the corner.

“The Chinese government are control freaks, they can’t stand any opinions they disagree with,” Katherine, a protester in her late twenties and a civil servant, told AFP before police moved in.

“In Xinjiang they are doing what they are doing because they have the power to do so. When they take over Hong Kong they will do the same,” she added.

China cracked down on Uighurs and other Muslim minorities after a series of deadly attacks in the area.

It bristles at any criticism of its policies in Xinjiang.