But Lam was arrested early on Tuesday morning after closed-circuit television footage showed he had left Yau Ma Tei, a busy downtown district, safely on public transport on Thursday afternoon, contradicting his claim he was kidnapped there in broad daylight.

“We held a press conference for his own safety,” Wu said following an emergency meeting of the party’s central committee on Tuesday.

Asked if he still trusted Lam, Wu said it would be unfair to both his party and Lam if he were to draw any conclusions at this stage. He said he hoped police would complete their probe into the case as soon as possible.

Wu did not directly address whether the saga would compromise the credibility of the Democratic Party.

Hong Kong democrat Howard Lam rebuts his kidnapping claim doubters

He would not comment further on the incident, citing the ongoing police investigation, but pledged to offer a public explanation once the results of the probe were out.

Hong Kong leader Carrie Lam Cheng Yuet-ngor said on Tuesday she had “every confidence” in the police investigation. It was important for the public to trust the city’s law enforcement bodies, which would conduct the probe in a “very fair” and “open” manner, she said.

Speaking before her weekly Executive Council meeting, the chief executive was asked to comment on the activist’s arrest.

“The case of Mr Lam is purely a case under investigation by police. From the beginning until this moment, I have had absolutely no involvement in this case, and I have every confidence that our police colleagues will fully investigate, of course, with the cooperation of the person involved. So I have no particular comment.

“The important thing is for society to have confidence and trust in our law enforcement bodies. They will investigate in a very fair ... and open manner,” she added.

Hong Kong democracy activist in custody, police search home after ‘false’ kidnap claim

The chief executive also said: “I think when someone claims that he was abducted and tortured, society will have its own judgment after seeing the evidence ... I appeal to everyone not to make unnecessary speculation on this.”

Critics of the plan had said Howard Lam’s claim showed Hong Kong people’s freedom would be further compromised under the “co-location” arrangement for the checkpoint at the rail station.

Asked if and how the activist’s claim would affect the joint checkpoint scheme, Carrie Lam said: “We will continue to explain the co-location plan [to the public].”

“It has a very sound legal foundation, and I was notified that lawmakers had passed a motion in support of it – I believe this reflected public opinion to some extent,” she added, in reference to a motion initiated by the pro-establishment camp in Hong Kong’s legislature at a meeting last week.

Lawmaker says abduction claim to have no effect on Hong Kong joint checkpoint views

Howard Lam claimed he was forced into a van on Portland Street on Thursday at about 4pm and taken to a building at an unknown location where he was tortured by his abductors, who punched staples into his legs.

He said he found himself dumped at a beach in Sai Kung in eastern Hong Kong sometime between 1am and 2am, and took a taxi home. He held a press conference, backed by his party, to tell his story at 11am, before reporting the case to police.

But FactWire news agency published a report on Monday night directly contradicting Lam’s version of events, using nine pieces of CCTV footage to reconstruct the incident. The activist was then arrested on Tuesday at about 12.30am for allegedly misleading police with his kidnap claims.

A police source speaking to the Post denied that the force had arrested Lam only because of the FactWire report.

He said officers had planned to take action after the force learned where Lam had been during the nine “mysterious” hours between his alleged abduction and release.

“We had also obtained those [CCTV] clips in prior days and saw that Lam took public transport to leave Mong Kok. We knew that he might have given us a false statement and been misleading us,” the insider said.

“We are obtaining more footage from around the city to trace where Lam was in the nine hours when he claimed he was tortured during his so-called detention ... As FactWire released the footage, we were forced to take action and arrest Lam earlier.”

The insider said the force would seek legal advice from the Department of Justice to see if charges should be laid before Lam leaves for the United States to study later this month.

Despite news of Lam’s arrest, Democratic Party veteran Albert Ho Chun-yan defended the decision to go public with his abduction claim.

Hong Kong police investigate democracy activist’s claim he was kidnapped and tortured by mainland China agents

The former lawmaker said Lam had approached party members for help at 3am on Friday with severe-looking wounds.

“Although I didn’t know about this until 8am, I think it was a very natural decision that we made this public,” Ho said on an RTHK programme. “If somebody so wounded comes to seek help and complain, you assume the story is true and that the public should know.

“I don’t think we have done anything wrong.”

Ho said he had spoken with Howard Lam briefly after the FactWire report was released, and that Lam insisted he was not the person in the CCTV footage.

The former lawmaker said he was surprised that Lam had gone from being a victim to a suspect, but added that he would not come to a conclusion about the case until police had shown more evidence to prove Lam had not been kidnapped. He urged police to find out the truth as soon as possible.

Democratic Party lawmaker Lam Cheuk-ting said the person in the CCTV footage did look like Howard Lam based on the clothing and body shape, but added that Lam had flatly denied that it was him.

“I cannot conclude whether it is him in the footage or not,” Lam Cheuk-ting said. “No matter which way I make a comment, it will be unfair to the case.”

He said the party had contacted a lawyer right after Howard Lam’s arrest, and added that the party would provide help to Lam’s wife as far as possible.