Hong Kong (CNN) -- "Please set him free" read the plea in stark black print on the front page of the New Express newspaper based in the southern Chinese city of Guangzhou.
In a bold move, the paper openly defied Chinese authorities this week by asking for the release of one its reporters, who has been detained by police in Hunan province.
The move garnered sympathy online and China's media regulator vowed to protect "lawful reporting rights," according to the state-run China Press and Publishing Media group.
Chen Yongzhou was arrested on Saturday, police in the provincial capital Changsha said, months after the newspaper ran stories by Chen that claimed that a Hunan-based company Zoomlion Heavy Industry Science & Technology falsified sales numbers.
The state-run company, which did not respond to a call for comment, makes construction equipment.
The police said he had been arrested for damaging a business' commercial reputation, without giving further details. A police spokesman in Changsha contacted by CNN declined to comment.
In May, Zoomlion temporarily suspended trading in its Hong Kong-listed shares to address allegations made in one of Chen's articles. In a statement to the Hong Kong stock exchange, it said that all allegations relating to fictitious sales were "false, groundless and misleading."
The paper said on Wednesday that it had verified all of Chen's stories about Zoomlion and only found one discrepancy: He wrote the company spent 513 million yuan on advertisements, when that money had been spent on "advertisements and entertainment."
"If Brother Policeman can find any evidence of shabby reporting on our part, please make notice of it and we will gladly doff our hat," the newspaper said according to a translation published by the University of Hong Kong's China Media Project.
"Because we still believe that — some day, at least — you will have the same full respect for the law that we have."
Open resistance by Chinese media against intimidation by authorities is rare but not unprecedented.
In January this year, crowds gathered in Guangzhou in support of a protest by journalists against alleged government censorship. Journalists at the Southern Weekly paper claimed that an editorial calling for political reform was rewritten by censors as a tribute to Chinese Communist Party rule.
The New Express released a statement from Chen's wife, who said that Chen was taken from his home in a black Mercedes Benz with Hunan license plates. "My... life stopped at the moment," she said.
On social media site Weibo, Chen's colleagues described him as a talented and hardworking business reporter, who ate instant noodles and couldn't afford to take his wife to Pizza Hut.
"We are very grateful that the society has given a lot of attention on this," a spokesperson for the New Express newsroom told CNN.
CNN's Feng Ke in Beijing contributed to this report