Hong Kong chief executive Leung Chun-ying on Monday hit out at the 'disappearance' of a fifth bookseller and publisher linked to a bookstore known for selling political gossip about the ruling Chinese Communist Party.
But he stopped short of confirming that the owners and employees of Causeway Bay Books and its parent publishing company had indeed been detained by Chinese police or their agents in Hong Kong, which has maintained its status as a separate jurisdiction since the 1997 handover to China.
"No other law enforcement agencies outside of Hong Kong have such authority," Leung, who has often been accused of kowtowing to Beijing, told reporters.
"In Hong Kong, the only people who can exercise the power of the law are our legal enforcement agencies of the Hong Kong Special Administrative Region Government," he said. "The law protects the rights, including the freedom and safety of everybody in Hong Kong."
"It would be unacceptable if mainland law enforcement agents enforce laws in Hong Kong because this violates the Basic Law," Leung said, in a reference to the territory's mini-constitution.
Leung told reporters that the government is "concerned" about the case, and will be following up on it.
Lee Bo, 65, who manages Causeway Bay Books, was last seen last Wednesday in the Chai Wan warehouse of Mighty Current, the publishing house that owns the shop, the South China Morning Post (SCMP) reported on Monday.
Four of his business associates, publisher Gui Minhai, general manager Lui Bo and colleagues Cheung Jiping and Lam Wing-kei have gone missing under similar circumstances since October, although some have called to let their families know they are alive and well, suggesting they are now in detention in China.
Rights lawyer and pan-democratic lawmaker Albert Ho said the booksellers' disappearances are likely linked to a planned book on President Xi Jinping's love life.
"It probably has to do with ... a book containing a story about a girlfriend [of Xi's] ... from some years ago," Ho told a news conference in Hong Kong on Sunday.
"The publishers were warned not to publish this book ... [which] probably hasn't gotten as far as the printing stage yet," he said.
In an interview with RFA, Ho said the case of the missing booksellers is the latest in a long line of assaults on Hong Kong's traditional freedom of expression and publication.
"The mainland is targeting our publishing industry and our journalists in a policy that could be described as white terror," Ho said.
"This has been going on for some time now, and now we can see the long arm of Chinese law enforcement reaching into Hong Kong."
Retaliation and protests
The hacker group Anonymous has vowed to attack Chinese government websites in retaliation for not allowing Hong Kong to maintain the high degree of autonomy it was promised before the handover, according to a video posted to YouTube.
The 'disappearances' have sparked protests in Hong Kong, as well as growing calls for the government to investigate whether the "one country, two systems" principle agreed with the city's outgoing British rulers had been violated.
Lee’s wife told Hong Kong's Cable TV that her husband had called her from neighboring Shenzhen the night he disappeared, speaking Mandarin rather than the couple's native tongue, Cantonese.
"He said he will not be coming back any time soon. He said he was assisting in an investigation," she said.
"I asked him if it was about the previous cases, he said yes. It was about the missing [associates]," she said, in comments translated by the SCMP, which also quoted Hong Kong police sources as saying they had no record of Lee going through immigration on his way out of the city.
Richard Choi, of the Alliance in Support of the Patriotic Democratic Movement in China, said there are fears that the five men may be in extrajudicial detention.
"We don't know where these people are, and that is a serious violation of their human rights," Choi told RFA. "[Lee's] wife said he called her from Shenzhen, but how did he get there?"
"It is likely that he was illegally kidnapped by the Chinese police or the state security police in Hong Kong, which is a serious violation of the one country, two systems principle," he said.
Lawmaker and Labour Party chairman Lee Cheuk-yan said the idea that Chinese law enforcement could act of their own volition in Hong Kong was "terrifying."
"If we have one territory, two policing systems, then this is really asking for trouble, and it is a total violation of the Basic Law," he said.
‘Mountain out of a molehill’
While Beijing has made no comment so far on the 'disappearance' of the five men, the Global Times newspaper, which has close ties to the Communist Party, said Hong Kong people were "making a mountain out of a molehill" by speculating on Lee's fate.
"The hottest theory is that Lee Bo was detained by mainland law enforcement personnel in a so-called cross border operation," the paper said in a signed commentary article on Monday, pointing to the content of books sold in Causeway Bay Books as a contributing factor.
"A lot of the books they sold harbored malicious content which constituted a serious threat to the right of reputation," it said, without detailing whose reputation had been threatened.
It said such books had begun to circulate across the internal border in mainland China, where political writings are tightly controlled by party censors, "acting as a source of political rumors and causing a certain amount of pernicious impact."
The article, signed by Shan Renping, accused the bookstore of peddling "forbidden books" deliberately targeting mainland Chinese tourists who then bring the books back home with them.
"Some people are crazy enough to want to turn Hong Kong into the last bastion of political opposition to Beijing," it said.
Inquiries made by RFA with Beijing's Central Liaison Office in Hong Kong on Monday had met with no reply by the time of writing.
In May 2014, a court in the southern Chinese city of Shenzhen on Wednesday handed a 10-year jail term to 79-year-old Hong Kong publisher Yiu Man-tin after he edited a book highly critical of President Xi Jinping.
Earlier this year, the Central Liaison Office acquired control of Hong Kong's Sino United Publishing Co. in a move that gave it control of 80 percent of the book publishing market in the territory.
The liaison office already owns a number of Chinese-language media, including the Wen Wei Po, Ta Kung Pao and Hong Kong Commercial Daily newspapers, as well as the online Orange News.
Reported by Dai Weisen for RFA's Cantonese Service, and by Xin Lin for the Mandarin Service. Translated and written in English by Luisetta Mudie.