Beijing  - China has executed four Tibetans convicted of murder, arson and other violent crimes during anti-Chinese rioting in March 2008, a Tibetan rights group reported on Thursday.

The four men were executed on Tuesday in Lhasa, the capital of China's Tibet Autonomous Region, the Tibetan Centre for Human Rights and Democracy (TCHRD) quoted local sources as saying.

The executions were not reported by any state media, and it was not known if the death sentences were reviewed by the Supreme People's Court as required under Chinese law.

TCHRD said the body of one of the men, Lobsang Gyaltsen, was handed over to his family following the executions, which were reportedly supervised by the Lhasa Intermediate People's Court.

Lobsang Gyaltsen and another man executed on Tuesday, who was identified by the single name Loyak, were sentenced to death in early April, state media reported.

Lobsang Gyaltse was convicted of setting fire to two clothes shops in downtown Lhasa, causing the death of the owner of one shop, the government's official Xinhua news agency said in April.

Loyak was sentenced to death for setting fire to a motorcycle dealership, resulting in five deaths, the agency said.

TCHRD condemned the reported executions and urged China's ruling Communist Party to "show restraint and to grant its citizens fair trials and to abide by the basic human rights of all of its peoples, regardless of their ethnicity."

The group is based in the Indian hill town of Dharamshala, which is home to the Tibetan government-in-exile and the Dalai Lama.

Stephanie Bridgen, director of London-based Free Tibet, issued a statement condemning the reported executions.

"The executions are an outrage," Bridgen said. "It is impossible to have any confidence that even the most basic legal norms were observed before the Chinese state sanctioned and carried out the killing of these four Tibetans."

Violence erupted on March 14 last year in the Tibetan capital following anti-Chinese protests initially led by Buddhist monks.

According to Chinese officials, 19 people died in the riots but Tibetan exile groups said more than 100 died.

Dozens more Tibetans were sentenced to long prison terms or suspended death sentences earlier this year for offences linked to the rioting, state media reported.(dpa)