Authorities in China's eastern province of Zhejiang have handed down prison sentences to two men for selling "banned" political books from Hong Kong, as the ruling Chinese Communist Party continues its campaign against any form of political dissent.
Dai Xuelin, social media editor at the Guangxi Normal University Press, was handed a five-year jail term by a court in Zhejiang's Ningbo city, while his business partner Zhang Xiaoxiong was jailed for three-and-a-half years, Hong Kong's South China Morning Post newspaper reported.
The pair had been found guilty by the court of "illegal business operations," and their conviction came as part of the same investigation that targeted the five Hong Kong booksellers linked to the now-shuttered Causeway Bay Books store and its Mighty Current publishing imprint, the paper said.
The sentences were handed down earlier this month after a secret trial found that they had bought Hong Kong-published books not authorized for sale across the internal border in mainland China.
A source close to the business told RFA that the pair had been traveling to Hong Kong to buy the books directly, and had been targeted by a nationwide police investigation that questioned "large numbers" of people.
"This is all part and parcel of the Causeway Bay Books case, which has become a really big case now, and the authorities are in the middle of strike hard campaign against it, involving both customs and police," the source said.
"It's bad enough just selling these books privately, among friends, but doing it in bulk is bound to meet with a harsh response," he said.
One person contacted by RFA confirmed he was questioned as part of the investigation, but declined to comment on the case, citing "huge pressure."
An employee who answered the phone at the Guangxi Normal University Press asked for questions to be e-mailed, but no response was made to the e-mail on Saturday.
Among the books named in the indictment was How the Red Sun Rose, a historical analysis of the role of late supreme leader Mao Zedong in the rise of the Chinese Communist Party during the 1940s, before the founding of the People's Republic of China in 1949.
Using official Communist Party archives, the book details Mao's role in a series of factional struggles and internal "purges" during the period.
Two of the five Hong Kong booksellers reported having been taken to Ningbo for interrogation following their return to the former British colony.
One of the men, Lee Bo, is a U.K. national who the British government said was "involuntarily removed" from Hong Kong for the investigation.
Another Causeway Bay bookseller, Swedish national Gui Minhai, is still in detention at an unknown location after being removed from his holiday home in Pattaya, Thailand, in October 2015. Three others have been conditionally released and allowed to return to Hong Kong.
Books sold online
Nanjing-based author Jiang Chun said the jailing of the publishers in Zhejiang comes after authorities in Guangxi detained the former head of the Guangxi Normal University Press on "bribery" charges last May.
He Linxia was detained after he published a number of cutting-edge titles under the publisher's Lixiangguo imprint, including Gao Hua's book.
The Lixiangguo titles weren't published through traditional channels, but were sold via the online auction site Taobao, using an account which the authorities later shut down, sources told RFA at the time.
"The authorities did a clean-up of this publishing imprint last year, but they have gone too far," Jiang said. "[Dai] was selling so-called banned books from the Causeway Bay Books store, but at most he should have received a warning. Sending him to jail for five years is too harsh."
"How the Red Sun Rose was written by Gao Hua, who was a history professor here in Nanjing," he said. "This book was very well received in academic circles here in China, but it seems that telling the truth and recording history are crimes."
"They only want you to sing [the party's] praises."
Shenzhen-based online author Tian You said there are currently political purges afoot in Chinese academia that recall the denunciations of the Cultural Revolution (1966-1976).
"If they carry on like this, it will basically be the Cultural Revolution all over again," Tian said. "I was locked up for five days over this last year."
"What did I do? I just criticized their stupidity by saying that nobody would pay any attention to those books if they just allowed them to go on sale," he said.
"As soon as they start arresting people, they are pretty much doing the selling for them, aren't they? They said I had insulted [the government]."
"I think that if they carry on like this, something big is going to happen," Tian said.
Retired Shandong University professor Sun Wenguang said many Chinese authors are now forced to get their books published in Hong Kong.
"There's no freedom of publication in China at all," Sun said. "Some authors just send their books straight to Hong Kong on completion, so the Chinese Communist Party uses 'illegal business operations' as a way of stopping those books finding their readership."
"There are a lot of books published in Hong Kong and Taiwan getting passed around now, all of which are treated as illegal business operations, and severely punished," he said.
The cross-border detentions and interrogation of the five Causeway Bay booksellers has been cited by U.S. and European officials as evidence that Hong Kong is losing the "high degree of autonomy" and traditional freedoms guaranteed for 50 years under the terms of the 1997 handover from the U.K. to Chinese rule.
Reported by Wong Siu-san and Lau Siu-fung for RFA's Cantonese Service, and by Xin Lin for the Mandarin Service. Translated and edited by Luisetta Mudie.