A teacher who posted photographs on the internet of schools which collapsed in the Sichuan earthquake has been sent to a labour camp for a year, a rights group said yesterday.

Liu Shaokun was ordered to serve a year of "re-education through labour", according to Human Rights in China. The system does not require a charge or criminal trial and is not subject to court appeals. He is believed to be the third person held after questioning why so many schools were destroyed in the earthquake.

Scores of schools across the southwestern province collapsed following the 7.9 magnitude shock. In many cases, buildings around them remained intact, prompting questions about the quality of their construction. The authorities initially responded to public outrage by promising an inquiry into whether shoddy building work was linked to corruption.

But they have subsequently silenced critics, ordering state media to avoid the subject and preventing parents from protesting. In recent weeks police have dragged grieving relatives away from demonstrations in some areas. Families have also been pressed to take compensation in exchange for signing contracts which include commitments not to protest or attempt to sue the authorities.

"Instead of investigating and pursuing accountability for shoddy and dangerous school buildings, the authorities are resorting to re-education through labour to silence and lock up concerned citizens like teacher Liu Shaokun and others," said Sharon Hom, executive director of Human Rights in China.

The group said that Liu, a teacher at Guanghan middle school in Deyang city, was detained on June 25 for "disseminating rumours and destroying social order." His wife, who has not been allowed to see him, was told last week that he had been sent to a labour camp. He had travelled through the quake zone taking pictures of the ruins of schools and circulating them on the internet, along with criticism.

The public security bureau in Deyang told the Guardian it was trying to find out more about the matter and the Guanghan city propaganda department said it had not heard of the case.

But an official with the general office of the Guanghan school where Liu worked told Reuters: "He was detained late last month by people from national security bureau for deliberately inciting families of victims to petition and disseminating anti-government rumours. They searched his home and found evidence."

The family of Huang Qi, a longstanding rights activist from Sichuan, said this month that he had been formally arrested for "illegal possession of state secrets" after helping bereaved parents and posting articles about structural failings of schools on his website.

China's human rights record and lack of political freedom are under increasing scrutiny with the Olympic games only days away. Yesterday a senior official from the International Olympic Committee admitted that colleagues had cut a deal to let Beijing block sensitive websites despite promises of unrestricted access.

Yesterday journalists at the main press centre were unable to access sensitive sites, including that of Amnesty International, which this week released a highly critical report on human rights in China.