HONG KONG -- A senior officer of Hong Kong police on Monday refuted again accusations by a Hong Kong lawmaker that undercover officers disguised as rioters and committed violent acts on the New Year's Day.

"Such accusations were utterly false and founded on fake news," Chief Superintendent Kwok Ka-chuen of Police Public Relations Branch said in a letter to Claudia Mo, a member of the Legislative Council of the Hong Kong Special Administrative Region.

Mo claimed that the police sent two undercover officers to vandalize shops in Wan Chai with the intention to use the incident to halt the protest on Jan 1 in a live Sky News broadcast.

In response, the police made a prompt clarification that police officers did not commit crime of any sort on Jan 1 and elaborated on the matter on the next day.

Kwok said in the letter that it was the violence of rioters, including blocking roads and trashing banks and shops, that led to an early conclusion of the public event, and stressed that the use of force of the police was appropriate and only reactive.

"The Hong Kong Police Force respect all citizens' right to assembly and association, and to express their opinion freely and without fear," Kwok said.