A forum user posted the idea of sharing made-up stories to negatively impact mainlanders' support for the Chinese government.
Formal head of the IPCC said it was unfair to burden the watchdog with the role, and supported the call for an independent commission of inquiry.
Hundreds of people gathered to commemorate the event and express their continued disappointment in police's handling of the incident.
Commissioner calls for tougher laws and more powers for watchdog to tackle 'weaponising' of personal data.
Protest-themed Chinese New Year bazaars have sprung up to raise money and morale for the pro-democracy movement.
Ventus Lau Wing-hong is a spokesman for Hong Kong Civil Assembly Team, which organised the rally.
A similar episode occurred in December when a reporter from Stand News had his ID card displayed in front of a live-streaming camera.
Tear gas was fired in Central to disperse protesters who had attended the demonstration in Chater Garden.
The traditional Lunar New Year fair in Victoria Park won't offer dry goods this year, but you can still find some quirky CNY goods elsewhere in Causeway Bay.
While most shops and restaurants had reopened, stores like Muji and Nike remained closed.