A leading vaccine maker said on Thursday that business news website 21cbh, which has been in the spotlight for alleged extortion by its journalists, tried to blackmail it but failed.

BioKangtai, a hepatitis B vaccine maker in Shenzhen, was wrongly suspected of being connected with the deaths of 17 newborn babies between Dec 13 and Dec 31. Authorities announced in January that none of the cases were linked to the vaccine, and BioKangtai's products were safe.

"The journalists of 21cbh issued a couple of stories concerning the cases, which were malicious to the company and distorted the facts," Miao Xiang, spokesman of BioKangtai, said in a media briefing.

After that, some intermediates and public relations companies contacted the company management and hinted they could handle the negative news, as long as they would "cooperate with them", Miao told media.

"They asked for several million yuan in return," he said. The company refused.

"Despite the company not paying, the distorted stories affected people's confidence in the hepatitis B vaccine, and the vaccinations dropped dramatically," he noted, adding that the reduction posed a big threat to newborn babies.

Miao said the company did not rule out the possibility of taking legal action against the website but did not specify the precise nature of the action.

Eight people, including the president and editor-in-chief of 21cbh, as well as the heads of two PR firms, were detained by police in Shanghai recently.

They were suspected of having extorted hundreds of millions yuan from more than 100 companies since November 2013, Xinhua News Agency reported on Thursday.

Xinhua quoted the police as saying that 21cbh and the two PR firms collaborated to extort money from these companies in return for favorable coverage and withholding negative news reports on the site. If companies refused, the website would publish negative information about the company.

Zhou Bin, editor-in-chief of the website, said he used to target companies that had not "established collaborative relations" with 21cbh and direct journalists to release negative news reports about them on the site, according to Xinhua's report.

When the companies involved came to 21cbh themselves or through a PR firm, the website would charge 200,000 to 300,000 yuan ($32,500) in the form of advertising contracts, in exchange for deleting the negative reports from the site, Xinhua reported.

According to Xinhua, Wang Zhuoming, another suspect and a reporter for the website, told the police: "Using negative news reports to extort companies is a hidden rule, and it's a collective action."

The list of victims covers listed companies and famous enterprises from Beijing, Shanghai.

Confessions of the suspects show "too many companies" were 21cbh's victims, but only a few told the police, according to Xinhua.

21cbh is run by Guangdong's 21st Century Media Co, which claims on its website to be "the largest professional media operator in the Chinese financial and business media industry".

chenhong@chinadaily.com.cn