Anger and tension on Hong Kong's streets spilled into bloody violence on Saturday (September 21) night.
In a video obtained by broadcaster TVB, men who reportedly disagreed with Hong Kong's protest movement can be seen being savagely beaten by protesters.
Local media said one of the victims had been cursing at protesters before he was set upon. After the attack, he said: "This is what justice has become".
More than three months of unrest have seen violence from both protesters and police.
On Sunday (September 22) one flash-point was a shopping mall in the New Territories town of Sha Tin, where the Chinese national flag was trampled on and burned.
What started as a peaceful gathering of hundreds chanting for Hong Kong's "liberation" descended into violence, with protesters trashing the mall and a neighboring subway station.
That prompted riot police to move in.
One protester, speaking before Sunday's clashes, said the movement needs to voice its demands in both non-violent and violent ways.
(SOUNDBITE) (Cantonese) PROTESTERS, CHONG SAYING:
"If you're asking how this movement will turn out I'd say it needs everyone's help. For example, organize an event like this, gather people of different ages, at various places to voice our demands. However there are some protesters who do it with force and they have clashed with the government. Both protesting methods are important, just like our demands, not one less."
The protests picked up in June over now withdrawn legislation that would have allowed suspects to be sent to mainland China for trial.
But it has morphed into a wider movement against the perceived increase of Chinese interference.
Protest demands include the release of all detained demonstrators and an inquiry into alleged police brutality.
China says it is committed to Hong Kong's "one country, two systems" arrangement and denies meddling.
But with just days until the 70th anniversary of the founding of the People's Republic, the protests continue to cause a headache for Beijing.