A Communist Party cadre who briefly rose to fame in China by denouncing official corruption has been relieved of his duties and placed under a form of house arrest while authorities investigate his conduct, friends and neighbors said Thursday.

The case of Huang Jingao, party secretary for Lianjiang county in Fujian province, demonstrated the potential cost of speaking out against China's pervasive corruption, despite repeated pledges from leaders in Beijing to prosecute city, county and provincial officials on the take.

Huang generated a national buzz in August when he wrote an open letter complaining that his efforts to investigate and prosecute corruption were being stymied by higher-level party and government officials because of what he called "the underlying rules" by which unscrupulous functionaries protect one another.

The letter, which was posted on the Web site of the People's Daily, the party's official newspaper, became an immediate sensation. Internet users across the country chatted about Huang's integrity. Editorialists in Beijing exulted in the airing of his charges by the party's own press. And ordinary Chinese, inured to official corruption, commented on his bravery.

But within a few days, the letter was taken down from the People's Daily site, and Huang was called on the carpet by party authorities in Fuzhou, the nearby provincial capital, 300 miles south of Shanghai. In a statement using 1960s-vintage Marxist-Leninist rhetoric, they accused him of "individualism" and ordered him to "do a complete self-examination."

In the weeks since then, Huang has been rendered unable to perform his duties as the county's party secretary and has been in effect replaced by his deputy, according to his friends and neighbors. Although he still has his title, he has been confined to his home or office, according to a source aware of the situation.

"In other words, Huang Jingao has been shelved," one acquaintance said.

Seven people have been detained for questioning as part of the investigation against Huang, a Lianjiang official said. One was a vegetable farmer who was urged to accuse Huang of accepting bribes, the official added, while another was a deputy of Huang's who went to Beijing in an effort to bring Lianjiang's corruption cases to the attention of national-level officials.

Huang's anti-corruption efforts centered on what he described as crooked deals in which officials took bribes to confiscate peasants' land and sell it at below-market prices to developers. Such land confiscations have become one of China's most common points of conflict.

Researcher Jin Ling contributed to this report.