BEIJING,  (Reuters) – Chinese security forces broke  international law when they used disproportionate force to  handle riots in Tibet two years ago, according to a report  released yesterday that quotes eyewitness accounts.

New York-based Human Rights Watch said Chinese forces  “opened fire indiscriminately” on protesters in at least four  cases when unrest hit Tibet in March 2008, and have conducted  large-scale arbitrary arrests since and tortured suspects in  detention.

At least 19 people died in the riots, which came a few  months before Beijing hosted the Olympics and sparked waves of  protests across Tibetan areas. Pro-Tibet groups overseas say  more than 200 people were killed in a subsequent crackdown.

The government has repeatedly insisted it used minimal  force. It has blamed exiled Tibetan spiritual leader the Dalai  Lama for instigating the violence, charges he strongly denies.

Human Rights Watch said it looked at accounts from more  than 200 Tibetan refugees and visitors, as well as previously  unreported official Chinese reports to get a clearer picture of  the unrest. “International legal standards limit the use of force by  states to that which is strictly necessary in order to protect  life or to apprehend perpetrators of violent crimes,” it said.

“In multiple incidents, eyewitness testimonies show that  Chinese forces acted in contravention of these standards and  broke international law — including prohibitions against  disproportionate use of force, torture, and arbitrary  detention, as well as the right to peaceful assembly.”

China’s Foreign Ministry did not respond to a request for  comment. Beijing strongly rejects all accusations of human  rights abuses in Tibet and says it respects local culture and  has pumped billions of dollars into developing an impoverished  region.