It was widely believed that the booksellers were detained in mainland China,[1][2] and in February 2016 Guangdong provincial authorities confirmed that all five had been taken into custody in relation to an old traffic case involving one of the detainees, Gui Minhai.

In his report to the British government and parliament in early January 2016, foreign secretary Philip Hammond said the incident was "a serious breach of the Sino-British Joint Declaration on Hong Kong and undermines the principle of one country, two systems".

These efforts were widely derided by commentators as a farce and a charade, as they failed to satisfy concerns over the breach of "one country, two systems" and its practical and constitutional implications.

[7][8] On 16 June 2016, shortly after he returned to Hong Kong, Lam Wing-kee gave a long press conference in the presence of legislator Albert Ho in which he detailed the circumstances surrounding his eight-month detention, and describing how his confession and those of his associates had been scripted and stage-managed.

Freedom of speech in Hong Kong is protected under Basic Law Article 27, and these independent publishers thrive as they cater predominantly to people interested in the machinations of mainland politics.

[17] In late 2013, Yiu Man-tin (姚文田), founder and chief editor of Morning Bell Press (晨鐘書局) and a Hong Kong resident, was arrested in Shenzhen after he had been tricked there.

[34] His wife filed a missing persons report with the police on 5 November and his family received a telephone call from him several hours later;[34] he refused to reveal his whereabouts.

[35] When filing the police report, they were referred to the Immigration Department, who said it was against privacy policy to reveal a person's records of entry and exit of Hong Kong without the subject's permission.

After the arrest of Yiu Man-tin and the disappearance of three of his colleagues, Lee went on record to say that their motive was purely economic, and that not setting foot in the mainland was the cost to bear for being in the publishing business.

[48] Lee Bo's disappearance spurred renewed interest about Lam Wing-kee, and his family received a police visit the same day after chief executive CY Leung spoke publicly on the case.

[49][15][1][21][50][51] Article 22 states that no department of the central, provincial, or municipal governments within China may interfere in the affairs which the Hong Kong Special Administrative Region administers on its own.

[34][53][54] In January 2016, after it was revealed that all five men were in mainland China, Lam expressed confidence in the sincerity and goodwill of the PRC government, and said that Lee Bo's disappearance was an isolated case that needed a swift resolution, but it did not amount to a breakdown of one country two systems.

[55] The American Chamber of Commerce asserted that with the rule of law, Hong Kong was still a preferable springboard to invest from, compared with Shanghai or Beijing, but nevertheless expressed concern at the disappearances.

[59] The allegations of prostitution, criticised by pro-democracy figures as character assassination, were carried by TVB on its prime time evening news as the leading item.

[63] Benny Tai and former chief secretary Anson Chan both said the case poses a genuine threat to the "one country, two systems" principle, which China ought to uphold.

[71] Singapore-owned Page One removed some of the books published by Mighty Current – in particular many titles focusing on Xi Jinping – from their retail outlet at Hong Kong airport.

[70] Richard Charkin, president of the International Publishers Association expressed "deep concern" for the missing men and called for their safe return home.

[74] American and European associations of publishers and booksellers – including PEN American Center, the Authors Guild and the Federation of European Publishers – jointly wrote to CY Leung, urging him to take action on the missing Causeway Bay booksellers and "request a formal assurance from Beijing that it will respect Hong Kong's autonomy and abide by the 1984 Sino-British Joint Declaration".

[60] Global Times, a tabloid subsidiary of People's Daily, wrote three successive belligerent editorials on the case,[57] an act viewed by Hong Kong media as an indirect recognition of China's role in the disappearances.

[73] Speaking anonymously, a senior foreign diplomat in Hong Kong revealed that at least six countries had expressed their concern and asked for information regarding the disappearances as at 23 January 2016.

[68] Reuters revealed that fifteen ambassadors or consuls were concerned about the broad interpretation of Chinese nationality, and that the denial of consular access to a Swedish and a British passport holder was a violation of international treaties.

[97] Chinese state media published an interview on 17 January where Gui Minhai confessed to causing the death of a student whilst driving under the influence of alcohol in 2005 and for which he supposedly received a two-year suspended sentence.

[102] The confession has been received with incredulity, and many of the facts surrounding his mysterious disappearance from Thailand, including the release of the video three months after him vanishing, have been called into question.

[101][103] The president of the Legislative Council of Hong Kong, Jasper Tsang, said: "the China Central Television (CCTV) report [and broadcast of Gui Minghai's confession] did not seem to be able to calm the public.

[104] Human Rights Watch was quoted in the Wall Street Journal saying: "Given that Gui has been held nearly three months incommunicado, in a secret location, and without a lawyer, his confession on state-controlled TV lacks credibility.

[112] After his wife reported his disappearance to the Hong Kong police, a letter purportedly handwritten by Lee Bo was faxed to Taiwan's Central News Agency on 4 January 2016, explaining that he had "returned to the mainland using my own methods" to work with "concerned parties".

He held to the story that was in the letters published by Sing Tao, saying he "resorted to illegal immigration" to get to the mainland "to cooperate in a judicial investigation" as he did not want to draw attention to his visit.

[121][122] On 4 February 2016, provincial authorities in Guangdong confirmed that Lui Bo, Cheung Jiping, and Lam Wing-kee had been taken into custody in relation to a case involving Gui Minhai.

[125] Phoenix TV, citing police sources, said the three men showed "good attitude" by confessing and might be allowed to return to Hong Kong within the week while they await trial.

[136] Sing Tao Daily published a retort by a case officer in Ningbo, saying that Lam and his girlfriend had signed confessions to having been engaged in "illegal business operations" and agreements not to hire lawyers nor see their families.