The Chinese government announced Sunday it had detained the commander whose forces opened fire on residents protesting land seizures in a town near Hong Kong, making a rare admission of police misconduct in what could be the deadliest attempt to suppress demonstrations in China since the 1989 Tiananmen Square massacre.

The announcement came a day after local authorities first acknowledged the violence last week in Dongzhou, about 125 miles northeast of Hong Kong in Guangdong province. State media said three people were killed and eight wounded in the clash. Witnesses have put the death toll as high as 20.

The main official newspapers in the provincial capital of Guangzhou said that "the commander at the scene dealt with the situation improperly and brought about mistaken deaths and accidental injuries," and that he has been detained by local prosecutors as part of a criminal investigation.

The report asserted that the commander's actions were made "under particularly urgent circumstances," and said legal responsibility should be borne by "a tiny minority of troublemakers" who led the protests over compensation for farmland confiscated to build a wind-powered electricity plant.

The report did not identify the commander or his unit, nor did it specify how he mishandled the protests. Residents have said that anti-riot police and members of the People's Armed Police, which is under Chinese military command, participated in the incident, firing handguns and automatic rifles at farmers and fishermen who attacked them with gasoline bombs and explosive charges.

The commander was placed under a form of detention that falls short of formal arrest and allows prosecutors to question suspects to determine whether criminal charges are appropriate.

If the commander is punished, it would represent an almost unprecedented concession by China's ruling Communist Party, signaling a desire to calm angry residents and warn police officials across the country to refrain from the unnecessary use of lethal force.

The Chinese leadership continues to defend the military assault on the student-led, pro-democracy demonstrations in Tiananmen Square in June of 1989, in which hundreds, if not thousands, were killed. But in the years since, the government has sought to defuse protests without resorting to force, usually by targeting leaders for arrest while offering concessions to others. It has also equipped police with tear gas, truncheons and other nonlethal weapons and instructed that they be used instead of guns when force is deemed necessary.

The clash in Dongzhou, a community of 10,000, involved a sharp escalation from tactics Chinese police have used against spreading social unrest in Chinese villages and industrial suburbs. Witnesses said officers repeatedly fired AK-47 assault rifles into a crowd during nighttime protests.

The commander's detention came as villagers complained that local authorities were trying to cover up the scale of the violence by refusing to allow relatives to retrieve the bodies of the dead and instead hiding them by cremating them or dumping them in the ocean. "They say three villagers were killed and eight were injured, but I don't believe their numbers," said one resident, who spoke on condition of anonymity. "We still have so many villagers who have been missing for several days, and one no knows whether they are dead or alive. . . . What we need from the government is justice!"

He and other residents reached by telephone dismissed the detention of the commander as an empty gesture. "They can't solve the problem this way. They just can't detain a commander. It's not that simple," said one villager. "More people should be held responsible and punished." Residents said the village was calm but tense, with police patrolling the streets and everyone staying indoors. The government has sealed off the village, barring people from entering or leaving and cutting off some phone calls with outsiders. Internet access has also been limited to local Web sites, residents said.

State media have blamed three villagers it called "instigators" for the incident, saying they incited residents to throw explosives at the police. Local fishermen normally use the explosives to stun fish in the adjacent South China Sea.

Police officers check identities and search cars traveling toward Dongzhou, in southern China. Police sealed off the town after firing on residents protesting confiscation of land for a wind-powered electricity plant last week. State media say three people were killed.