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By Sui-Lee Wee
BEIJING, Oct 10 (Reuters) - A Chinese investigative journalist who has accused officials of corruption has been arrested, his lawyer said on Thursday, becoming the latest in a series of government critics to be swept up in Beijing's crackdown on rumours.
Liu Hu, a reporter with the Guangzhou-based newspaper New Express, was arrested on a charge of defamation on Sept. 30, said his lawyer, Zhou Ze. Liu had been detained in late August in the southwestern metropolis of Chongqing on suspicion of "fabricating and spreading rumours".
China's crackdown on online "rumour-mongering", widely seen as a tool to halt criticism of the ruling Communist Party, has chilled political discourse, with high-profile bloggers saying they have reined in sensitive postings for fear of detention.
Lawyers and activists called the crackdown a significant, if crude, expansion of powers to police the Internet and a blow to those who rely on microblogs to disseminate information that is often not monitored as strictly as traditional media.
On July 29, Liu accused Ma Zhengqi, deputy director of the State Administration for Industry and Commerce, of dereliction of duty during his time as party secretary of a local district in Chongqing. Liu had posted these allegations on his microblog.
The administration said it had been informed of the accusation but made no further comment, according to the Beijing Times newspaper.
Zhou called the charge against his client a "speech crime" and said the government could be retaliating against Liu because he detailed specific allegations against a wide range of officials, including many senior ones, across many provinces.
Liu's information came from his reporting and through his network, Zhou said, adding that Liu had no reason to suspect the veracity of the content.
"It's impossible that passing on this information constitutes the deliberate spread of false information or the intentional fabrication and transmission of information," Zhou said. "Therefore it doesn't constitute defamation."
Liu's microblog account has been deleted.
Officials in Chongqing could not be reached for comment.
Chinese President Xi Jinping has made fighting graft a top theme of his new administration, and has specifically targeted extravagance and waste, seeking to assuage anger over corruption and restore faith in the party.
While the party has encouraged people to use the Internet to expose graft, it has detained activists who have called for officials to publicly disclose their assets.
Zhou said he believes the Chinese government "is somewhat uneasy" about people using the Internet as a tool to fight corruption.
Wary of any threat to its authority or social stability, the party has also stepped up its already tight controls over social media to limit public discussion of sensitive political issues.
In September, the government unveiled tough measures to halt the spread of what it called irresponsible rumours, threatening terms of three years in jail if untrue postings online were widely reposted.
"Weeks after the government passed a new rule criminalizing 'online rumours', a well-known whistleblower is arrested for defaming officials -- the message cannot be clearer, and it is likely to further silence Chinese netizens who are already quite worried," said Maya Wang, a researcher at Human Rights Watch. (Additional reporting by Beijing Newsroom; Editing by Clarence Fernandez)