Cai Lujun published four articles on an overseas Web site last year, in which he detailed the unfair levying of taxes and fees from rural residents of the northern province of Hebei, a Hong Kong-based human rights group said in a statement.

Cai, 35, was detained on Feb. 21, and sentenced at the end of October by the Shijiazhuang Intermediate People's Court, the Information Center for Human Rights and Democracy in China said.

His articles were titled "The Timetable for Chinese Democracy," "Miserable Second-Rate Citizens," "On the Current Political Monopoly and its Harmfulness," and "Outlines for Building and Governing the Country."

In a recent interview with RFA, Chinese economist He Qinglian said the Chinese government had recently launched a major overhaul of its existing system for monitoring Internet usage by its citizens, moving away from traditional firewalls and towards a centralized monitoring and control system.

"This monitoring system was jointly built by China's Ministry of Public Security and the Ministry of National Security," He said. "The initial investment for this project has reached as high as U.S. $800 million."

He, a former editor with the Shenzhen Legal Daily newspaper, said the system was among the most advanced of its kind in the world. "This is an attempt to establish a completely new centralized monitoring system after the firewalls installed in the 1990s began to lose effectiveness," she said.

Hong Kong-based OPEN Magazine executive editor Cai Yongmei told RFA that people turn to the Internet as a forum to discuss their issues with the Chinese government, which prohibits them from open demonstrations.

“People do not have an open channel through which to express their grievances, so they go to the Internet. They express their complaints about and criticism toward the darkness and corruption of the government as well as social injustices on the Internet and see this as comparable to rallying on the street. The government, on the other hand, sees this as a menace that must be controlled,” she said.

Cai's sentencing is the latest in a string of Internet-related political sentences. On Monday, a High Court in Beijing upheld eight-and 10-year sentences for four Chinese dissidents who posted their opinions online. The Information Center statement quoted relatives as saying they planned an appeal.

The Beijing High People's Court rejected appeals by Xu Wei, Yang Zili, Zhang Honghai, and Jin Haike. Yang's wife said the four were preparing a further appeal.