ANTHONY WALLACE/AFP/Getty Images(HONG KONG) -- A demonstration in Hong Kong turned combative on Monday when a group of pro-autonomy protesters, surrounded by thousands of others, began ramming and bashing the Legislative Council building, marring an otherwise peaceful pro-democracy march.

The incident coincided with the 22nd anniversary of Hong Kong's return to China from the British.

The protesters who attacked the building and the remaining thousands who kept marching both oppose an attempt to change a law that would allow for extraditions to nations including China.

Tension rose shortly after sunrise as hundreds of masked and helmeted protesters tried to disrupt the annual flag-raising ceremony that commemorates the handover. They clashed with police, who had set up an unprecedented security cordon around the Hong Kong Convention Center, at which embattled Hong Kong Chief Executive Carrie Lam presided over a televised toast.

In her first public appearance since her apology to Hong Kong's people, Lam shared an ill-timed split-screen moment with the gathered protesters as she tried to plead for a reset with the angry city she governs.

Lam previously had vowed to be more responsive to public sentiment after facing withering criticism in recent weeks.

"This has made me fully realize that I, as a politician, have to remind myself all the time of the need to grasp public sentiments accurately," she said in a speech at the city's cavernous convention center, insisting her government meant well. "I will learn the lesson and ensure that the government's future work will be closer and more responsive to the aspirations, sentiments and opinions of the community."

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