Senior Superintendent Chan Tin-chu, of the New Territories North regional headquarters, said the public had relied on “lopsided, twisted, misleading and flawed” online footage to form an incorrect view of the incident.

‘I considered resigning’: Hong Kong’s labour minister with opposition background

Police’s own investigation, he said, concluded that both sides were “on equal footing” in their use of force. Chan questioned, in particular, the description of the violence as “an indiscriminate attack” on bystanders and protesters returning home from clashes in the city, on Hong Kong Island.

“Calling it an indiscriminate attack is an inappropriate description,” he said.

Chan also said while police earlier suggested that officers arrived 39 minutes after they were notified, their investigation found it was 18 minutes.

As other victims accused police of rewriting history, the Democratic Party denounced the arrests as an act of revenge against Lam, who arrived at the scene that evening in Yuen Long after violence broke out and suffered injuries to his mouth that required 18 stitches.

Lam had gone on to vehemently and repeatedly criticise police for being absent and suggested they were in cahoots with the attackers, charges the force had denied strenuously.

On Wednesday, officers knocked on Lam’s door in Sha Tin shortly after 7am to arrest him, before subsequently detaining party colleague Hui and 14 others.

“Hong Kong has become such a ridiculous place,” Lam could be heard telling police, according to a video provided by the Democratic Party which captured the moments of his arrest.

Lam and 12 others, aged between 26 and 48, were detained on suspicion of rioting during the July 21 incident. Among them were a deputy director of a bank, social workers and chefs, some having suspected triad links.

Lam and Hui were also being investigated with two others, a man and a woman, over another protest on July 6, in which they were accused of unlawful assembly, criminal damage, perverting the course of justice, and accessing a computer with dishonest intent.

The incident dealt a blow to the police’s image after footage of the white-shirted mob hitting protesters and passengers inside a train carriage went viral online.

Hong Kong leader dismisses cabinet colleague’s ‘power’ jibe

Fuelling the anger and suspicion of police collusion with triads were still images and video of two officers seen walking away from the scene.

Police had said they were busy attending to other calls during that chaotic night. Police investigations had also proven to be slow-going, victims charged.

Before Wednesday’s swoop, police had arrested 44 people, some with links to triads, for their alleged roles in the attacks.

On Wednesday, Chan said those thought to be under attack had also provoked the white mob by telling them to fight, while others splashed water or threw objects at the attackers, thereby escalating the tensions.

Chan did not spell out Lam’s specific role, despite repeated grilling by journalists, saying only that the lawmaker had committed acts amounting to a rioting offence according to legal advice from the Department of Justice.

“Whether [Lam] has made a police report, how many press conferences he has held, how many Facebook posts he has disseminated, and how much political mileage he has gained are irrelevant to his behaviour at the scene,” he said, shrugging off any political motives.

The senior superintendent added: “We have never said who is the assailant and who is the defendant.”

Democratic Party to poll Hongkongers on whether to serve extended Legco term

In response to Chan’s statement that video footage had been one-sided, a former Stand News reporter, Gwyneth Ho Kwai-lam, who was among the first on the scene and was attacked during the incident, said her hour-long live video captured the men in white shirts and passengers being assailed but with no officers in sight.

“Even if the police arrest all the victims of the July 21 incident, you can never rewrite the history,” Ho said. “That was an indiscriminate attack and I believe anyone who watched my video would come to that conclusion.”

Democratic Party chairman Wu Chi-wai condemned police for taking “revenge” and accused the government of crushing dissent instead of trying to heal the rifts in society.

“We can see they are utilising all power and legal tools to turn black into white,” Wu said. “The government is turning themselves into enemies of the people. It is just outrageous.”

The pro-democracy camp called on all Hongkongers to wear black on Thursday to express their rage at “the police’s lie”.

Lawmaker Fernando Cheung Chiu-hung also said he saw the arrests as the government “declaring war on Hongkongers”.

Hong Kong opposition figures lose bid to stop police accessing mobile phones

Calvin So, a victim of the Yuen Long attack who was beaten by about 20 people outside Yoho Mall, was aghast at the police’s change of narrative.

“How can it be regarded as clashes between two rival camps?” asked the chef, who was attacked after finishing his shift that evening. “So, asking people to stop the attack also constitutes rioting?”

In an earlier interview with the Post, Lam said he went to Yuen Long after he was shown a video clip of a man being attacked outside a shopping centre there. He said he called a police public relations officer to stop the attack and that the violence had already ensued when he arrived. He broadcast the incident on Facebook, and was himself injured.

A Post review of a 34-minute video posted by Lam of that night’s incident found that Lam told the white mob to stay behind – using an expletive on one occasion – because he said police would come to arrest them.

He told protesters and passengers that he had called police, and that they should stay away from the mob. Lam also urged the mob to stop resorting to violence.

The video showed protesters and the white mob hurling objects at each other briefly. In another scene, some unleashed a water hose in the station’s lobby after members of the white mob began assaulting others.

Earlier this year, Lam and seven other injured people sued the police chief over the injuries they sustained in the attack, demanding a total of HK$2.7 million (US$350,000) in compensation.

Pro-establishment lawmaker Junius Ho Kwan-yiu, who shook hands with people dressed in white that night in Yuen Long but had denied any links to the attackers, said on Wednesday he welcomed the arrests. 

“I thought action would have been taken a long, long time before, but being late is better than never,” he said, dismissing claims the arrests were politically motivated. He suggested it was time to “remove the dead meat”, referring to the pan-democratic camp.

On Wednesday, Lam and Hui were also arrested over a rally held on July 6 last year, at Tuen Mun Park, where residents protested against what they said was the nuisance caused mostly by women from mainland China.

The women, who would sing in the park, also danced provocatively with their middle-aged male followers in public, their critics claimed.

On Wednesday evening, Hui was sent to North District Hospital in Sheung Shui after he reported feeling unwell.

Additional reporting by Emily Tsang and Clifford Lo