An unprecedented visit by China's premier to the bureau where ordinary citizens submit grievances about corruption and other problems has put the spotlight on a system widely regarded as broken but that Beijing is unlikely to fix.

State media reports showed Premier Wen Jiabao chatting with eight petitioners and speaking to staff at the central government complaints bureau on Monday afternoon. The government's Xinhua News Agency said it was the first time that a prime minister had met with ordinary petitioners in the 61 years of communist rule.

The publicity underscored a message Wen and other Chinese leaders like to show, especially ahead of next month's Lunar New Year — that they care about common people. But petitioners, who flock to Beijing by the thousands for redress, are usually given more brusque treatment, at times grabbed off the streets, held in unofficial detention centers known as "black jails" and sent home.

Beijing activist Zhou Li said Wednesday that at least three veteran petitioners who live in the capital were put under house arrest ahead of Wen's visit to the State Bureau of Letters and Calls — an indication his appearance was carefully stage crafted and that the people he spoke with were prescreened. Zhou said she'd never heard of the two petitioners named in state media reports, Wang Aiguo and An Jun.

"I think he may have wanted to go there to see the actual situation, what's really going on, but he still hasn't seen it," said Zhou, who has been helping petitioners for four years.

China Central Television said that during his visit, Wen urged citizens to voice their criticisms of the government and speak out about injustice. The report paraphrased Wen as saying the government must "create conditions that allow citizens to criticize and supervise the government, and enable government to responsibly resolve the problems and difficulties of the masses."

Wen has spoken before about giving the public greater freedom to voice anger and frustration over social problems such as corruption. The comments have been interpreted by some as a signal the leadership wants to more aggressively pursue political reforms, but concrete initiatives have yet to follow.

But the authoritarian leadership remains extremely wary of dissent that might threaten the Communist Party's monopoly on power. The government doesn't allow protests and routinely censors the media and Internet of any content that is potentially destabilizing or overly critical of the leadership.

The modern day petition system has its roots in the ancient tradition when commoners came to Beijing to appeal to the emperor. The current leadership, however, has often seen the system as troublesome, drawing to the capital too many people critical of the government. Legal scholars and rights activist say it is overwhelmed by complaints and symptomatic of a legal system that favors the powerful and connected over ordinary citizens.

Zhou and an overseas human rights activist said Wen's visit would likely be seen by petitioners as an endorsement of the system, prompting more people to file complaints.

Human Rights Watch researcher Phelim Kine said rural Chinese who feel marginalized in the economic boom are especially likely to turn to the system, which he described as "broken" because it fails to punish most abuses.

Kine cited a Chinese government-backed study from 2004 that indicated that only a tiny fraction — 0.2 percent — of a sample of 623 petitioners successfully resolved their problems through the petitioning system.

Orders from Beijing have put local officials across the country under pressure to bottle up petitions, since their performance is linked to the number of grievances filed — a sign of instability — from their locality. As a result, petitioners are sometimes detained before they can file their petitions and held in the makeshift "black jails."

Zhou said China should do away with the petition system and focus on reforming its judicial system to better handle people's problems.