Hong Kong police have asked Facebook to remove posts containing what they said were defamatory or unfounded allegations about their handling of anti-government protests, leading to accusations the force was interfering with free speech.

The Post has learned the social media giant will not delete any of the posts flagged by police despite two formal requests demanding it do so, which also included a call for the company to surrender all relevant information for investigation.

A message by opposition lawmaker Alvin Yeung Ngok-kiu, of the Civic Party, was among those complained about to Facebook.

Yeung said he had simply relayed what television media had reported on the shooting of a student.

Police raised concerns in a letter dated October 9 about posts published the previous month, including one alleging officers harassed a female protester during a car search in Tung Chung.

Another accused police of “killing Hong Kong people” in a campaign urging internet users to file complaints with the White House about what they called “police brutality”.

The force also highlighted a post tagged “live shot fired to kill citizen”, claiming the author of the message had sought to “make up facts” and distort the aim of the police operation.

In its letter, publicly available on its official website, the force said: “As a global social media platform, Facebook absolutely has the responsibility to ensure that contents dispatched by its users are factual and in the public interest.”

Facebook apparently did not heed the police’s demands and the force issued another letter last Thursday, expressing “extreme disappointment” with the company’s inaction.

In the second letter, the force referred to more “defamatory” posts and again insisted Facebook act decisively against “inaccurate reports” and posts that “provoke hatred”.

“We strongly demand the Hong Kong office of Facebook remove such content and hand over relevant information to police for further investigation,” the October 24 letter read.

On October 1, Yeung shared an online report about a young student being shot by police during a clash in Tsuen Wan under a social media post titled “live shot fired to kill citizen”.

“I was not approached by Facebook to remove the post. And I am not going to remove the post,” Yeung said on Tuesday.

“Hong Kong is a free society. And what I posted on my Facebook page was what I had seen on television.

“Hong Kong people do not need police to teach us what we should read on social media.”

Henry Chan Wan-hoi, a critic of the Hong Kong government who is described as an online influencer, said the force’s reaction amounted to interference with basic freedoms.

In a post on Tuesday, Chan wrote: “It is an open challenge to press and speech freedoms.”

A Facebook spokesman said: “We can confirm that we have received two letters from the Hong Kong police force regarding Hong Kong protest content on Facebook.”

A police spokeswoman said it was common practice for it to contact organisations and media to set the record straight on untrue or inaccurate reports, and to clarify its position. She declined to comment further.

In August, the international news outlet CNN apologised for a wrong headline that appeared on its website during its coverage of violent protests on August 25.

At one point, a headline reading “Police Use Petrol Bombs and Water Cannons Against Hong Kong Protesters” flashed on the screen.

Hong Kong police complained to say it was protesters who had thrown petrol bombs at police and that water cannons were only fired at barricades, not protesters.