BEIJING - Survivors of China's devastating earthquake last year face detention and harassment if they protest over collapsed schools, corruption claims and other grievances, Amnesty International said.

While Beijing is pouring billions of dollars into rebuilding towns in southwestern Sichuan province flattened by the May 12 quake, the government also has waged a less public campaign against citizens who blame more than natural destruction for the many schools that collapsed, killing thousands of children, the human rights advocacy group said.

By unlawfully locking up parents of children who died, the government is creating more misery for people who have said in some cases they lost everything in the Sichuan earthquake, said Roseann Rife of Amnesty in a statement emailed with the report released on Monday.

In the week before the anniversary of the quake, which killed around 80,000 people, the contention between state authorities and discontented survivors described by Amnesty could intensify.

On the weekend, several grieving parents of Juyuan, where a high school building toppled in the quake, told Reuters their plans to mourn their dead children were stopped by police.

The police and town officials told us that we should not make such a fuss, said one of the parents, Yang Rengui, whose son died in the school. Now many parents dare not speak.

Ahead of the anniversary, official media is praising the rebuilding effort and acts of selfless sacrifice.

But the Amnesty report highlights the tensions the quake left, pitting a one-party government that prizes control against people convinced neglect and graft made schools vulnerable and has tarnished rebuilding efforts.

Many of the tools of control Chinese authorities have honed to guard stability have been applied with particular intensity in quake-hit areas of Sichuan, Amnesty said.

Parents demanding inquiries into claims that corruption and lax quality-control weakened schools that toppled in the quake had been detained in black jails -- informal detention rooms in hotels and offices, Amnesty said.

Chinese lawyers and human rights activists who have offered help to grieving families had been intimidated and detained, and their efforts to bring cases to court stymied, the report said.

Rife said Amnesty had no firm estimates of numbers of detentions of parents and protesters.

But we assume we're only hearing about a small number of the abuses, she said from Hong Kong.

An official in the Sichuan government propaganda office said she had not seen the Amnesty report but rejected its claims.

This group has no right to criticize us, said the official, who refused to give her name. China has made many achievements in reconstruction, so why do they exaggerate and distort problems?

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