Twelve people involved in rioting in Tibet's capital Lhasa in March have been handed down "punishments" by the courts, China's state media says.

It is not clear what sentences the 12 received but reports said 42 people in total had been punished over the anti-China protests.

Peaceful protests that began on March 10 in Lhasa to mark the anniversary of a 1959 uprising against China's rule of Tibet escalated into widespread violence across the city on March 14 and spilled over into other parts of China inhabited by Tibetans.

With the Beijing Olympic torch relay running through Lhasa on Saturday, the rulings were made on Thursday and Friday. 

In April, authorities jailed 30 people for between three years and life.

'Questionable' trials

Exiled Tibetan leaders say 203 people died in the government crackdown.

China has reported killing one Tibetan "insurgent" and said "rioters" were responsible for 21 deaths.

On Wednesday, Amnesty International urged China to reveal what happened to people detained during the crackdown, saying more than 1,000 people were held but only a small number had faced "questionable" trials.

The Tibet issue was one of the major rallying cries for protesters who tailed the Olympic torch's month-long global journey before it came to China for the home run ahead of the August games.

Pro-Tibet activists as well as human rights and press freedom groups staged huge demonstrations in London, Paris and San Francisco, as well as smaller rallies in Australia, India and elsewhere.

The flame's shortened one-day stop in Tibet on Saturday is one of the most sensitive of the domestic route, which runs for thousands of miles over three months through every province and region of China.

China accuses Tibetans of targeting the Olympics, though the Dalai Lama, the exiled Tibetan spiritual leader, has repeatedly expressed his support for the Beijing Games.