A newspaper in Guangzhou published a front-page plea for the second day in a row calling for the release of one of its journalists by police in Hunan province.

The New Express' headline read, "Once again please set him free" on Thursday as it called on police in Changsha, capital of Hunan province, to free Chen Yongzhou and solve the problem within the legal framework.

Chen, who has been in criminal detention since Saturday, faces charges of "damaging business reputation" five months after the newspaper published his reports that Zoomlion Heavy Industry Science and Technology Development, a giant engineering company in Changsha, allegedly falsified its sales and revenue in Hunan, Hubei and Jiangxi provinces.

Changsha police said on Thursday that Chen's case is going through legal procedures, and the police will "handle the case according to law".

On Wednesday, The New Express carried a full-page editorial on the front-page under the headline "Please set him free".

"The reports on Zoomlion are normal news reports," the newspaper said in a subsequent statement. "It's the media's job and responsibility to report on problems and do the supervision. As a journalist with the paper's economic news department, Chen Yongzhou is merely doing his job."

Xinhua News Agency quoted an unidentified source with Changsha police on Wednesday as saying that the authority decided to put Chen under criminal detention after it found the newspaper and Chen "fabricated facts and printed 18 negative reports about Zoomlion without a proper verification process".

Changsha police declined to comment when contacted by China Daily on Thursday.

The All-China Journalists Association on Thursday urged local authorities to explain the controversial detention of a journalist who had reported on "financial problems" at a leading engineering company.

"We hope that related authorities in Hunan will present a convincing and justice-based explanation" on the matter," the association said.

The association said it will continue to track the detention of the journalist.

Chen's accusations that Zoomlion caused losses of State assets, falsified sales and financial figures, and had massive advertising costs were all fabricated, police said.

Changsha police invited the Hunan Diyang Judicial Identification Office to verify the losses in the 18 reports on Sept 17 and found Chen was suspected of faking and spreading false information, thus damaging Zoomlion's reputation and causing the company heavy losses.

In its statement, The New Express said the only error the journalist made was a reference to Zoomlion's 513 million yuan ($84.4 million) "advertising costs" instead of "advertising and operating expenses".

Du Feng, an assistant to Zoomlion's chairman, told Xinhua News Agency that Chen did not directly interview or contact the company before writing the reports.

The State General Administration of Press, Publication, Radio, Film and Television said it has paid close attention to the case and will stand up for the rights of reporters, the China Press and Publishing Journal reported on Thursday.

The decision by police to detain Chen has been questioned by newspapers, journalists and lawyers, as they doubted whether it is legitimate for the police to interrogate a journalist without formal charges and evidence.

"As evidence provided by The New Express suggested so far, what Chen did was part of his job," read an editorial by Beijing News on Thursday. "Police have so far failed to provide evidence of him breaching the laws.

"It is inappropriate to detain a reporter who is performing his duty on the presumption of guilt without concrete evidence."

Xia Nan, a lawyer with the Beijing Huayi Law Firm, said: "The reports on Zoomlion by Chen Yongzhou are public. (The police) need only to investigate the reports to determine whether he is guilty or not, rather than bringing him in for interrogation.

"If the police are handling the case fairly, they should at least allow him to be released on bail."

Xia said the lesson from the case is that journalists should take stricter measures to protect themselves.

"There should be a major adjustment regarding the method of gathering evidence and investigation, the selection of news materials and archiving, and the process of editors examining news stories," he said.

With a registered capital of 7.7 billion yuan and a workforce of more than 30,000, Zoomlion and its subsidiaries earned more than 90 billion yuan in sales revenue and paid more than 12 billion yuan in taxes last year. It is listed on both the Shenzhen and Hong Kong stock exchanges, according to the company's website.

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