Protests led by Buddhist monks against Chinese rule on March 14 last year gave way to violence.

Culture 'threatened'

Rioters torched shops and turned on residents, especially Han Chinese, who many Tibetans see as intruders threatening their culture.

At least 19 people died in the unrest, which sparked waves of protests across Tibetan areas.

Tibetan exile groups say more than 200 people died in the subsequent crackdown.

Ma Zhaoxu, a Chinese foreign ministry spokesman, did not give any details about the executions, but said they were linked to the violence.

Ma told reporters on Tuesday: "The procedural rights of the defendants were fully ensured.

"The two criminals who were executed had strictly conducted first and second trials and the Supreme People's Court examined and ratified the sentences."

China blamed the rioting on the Dalai Lama, the exiled Tibetan Buddhist leader, an accusation which the Dalai Lama denied.

Some exiled Tibetan groups have said that another two Tibetans were executed over the unrest that rippled out from Lhasa to other ethnic Tibetan regions.

Last week, 500 Tibetans, mostly Buddhist monks and nuns, marched with candles through Dharamsala in north India, where the Tibetan government-in-exile is based, denouncing what they said were executions of four Tibetans for the protests last