AFP / Getty Images A woman reads the New Express newspaper that on October 23, 2013 carried a full-page editorial with headline "Please release our man", in a library in Guangzhou, south China's Guangdong province.

New Express has a message for China’s censors: We may be small, but we have backbone. On Wednesday the Guangzhou-based newspaper published a front-page call for the release of its reporter Chen Yongzhou. Chen was detained by police in Hunan province while investigating a state-linked firm. The three-character headline, ‘Please Release Him’ was printed in a large, bold font above the fold. Hong Kong’s South China Morning Post called it an “unprecedented” demand for press freedom.

Chen was detained several days ago by police in neighboring Hunan province while investigating Zoomlion, a Hong Kong- and Shenzhen-listed company that is partially owned by Hunan’s government. In a series of 15 articles published between September 2012 and June 2013, Chen questioned the company’s financial stats, alleging that they overstated certain figures. (The company denies the allegations.) Chen is being held on charges of “damaging commercial reputation,” police said.

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The editorial strikes an unusually strident, even snarky, tone. “We always thought, if we reported responsibly, nothing could happen,” reads the piece. “But the facts show that we have been too naive.” Staff reviewed all 15 of Chen’s stories, it says, finding only one minor error. “Uncle Policeman, Big Brother Zoomlion,” the piece continues, “We beg of you, please set Chen Yongzhou free.”

The piece immediately made waves online and has already been re-posted more than 12,000 times on Sina Weibo, a popular microblogging site. Most of the comments seemed to support the paper’s stand. “If newspapers and journalists dare not tell the truth, there will be no truth,” wrote one netizen. Luo Changping, a well-known investigative reporter, agreed. “If Zoomlion insists Chen abused his media power, they should sue New Express, rather than ask the police to arrest the reporter,” he wrote. “Changsha police, release Chen now.”

It is too soon to know what’s next for Chen, or his paper. An unnamed executive from the New Express’ parent company, Yangcheng Evening Daily, said in an piece published Wednesday that the firm was “deeply concerned about Chen’s safety and civil rights.” David Bandurski, an editor at China Media Project, said that if Chen was formally charged, there was little chance of a fair trial. The aggressive business reporting conducted by New Express and other southern Chinese newspapers is a “bright light” in Chinese journalism, said Bandurski—a light he feared might dim should this “chill” take hold.

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