Bangkok  - Human Rights Watch on Thursday urged the Thai government to set up an independent commission to investigate recent politically-motivated violence "by all sides," including those responsible for this week's mayhem and last year's protests.

Thailand has been wracked by street protests for almost a year now, starting with the demonstrations led by the yellow-shirted People's Alliance for Democracy (PAD) that began in May 2008, and culminated with the closure of Bangkok's two airports for a week in November-December.

To date none of the PAD leaders - dedicated to the overthrow of last year's elected government that was openly supportive of fugitive former prime minister Thaksin Shinawatra - have been prosecuted or jailed for the damage they caused the country, including airport shutdowns which lost Thailand billions of dollars in tourism and export revenues.

A spate of new protests kicked off by the red-shirted pro-Thaksin United Front for Democracy against Dictatorship (UDD) on March 26, forced Thailand to postpone a regional summit last weekend and ended Tuesday with a government crackdown on street violence that left 123 people injured and two dead.

The two deaths have been blamed on the UDD. To date there has been no confirmation of the UDD's and Thaksin's claims that their followers were killed by soldiers, who used teargas, blanks and live ammunition to end the mayhem.

Three UDD leaders have been arrested and warrants are out for the arrest of 13 others, including Thaksin who has been living in self-exile since August 2008, avoiding a two-year jail sentence on an abuse-of-power charge.

Peace was restored to Bangkok's streets by Wednesday, but the threat of more UDD-led violence remains.

"Now that the protests are over, it is time for the government and protest leaders to make public commitments to end abuses and ensure that those committing violence are properly investigated and prosecuted," said Brad Adams, Asia director at Human Rights Watch.

"The many casualties during the protests cannot simply be forgotten or ignored," he added.

The rights watchdog called for setting up an independent commission to carry out "a prompt, effective, and impartial investigation" into the politically motivated violence over the past year and "hold those responsible accountable."

It said the commission should also investigate alleged abuses perpetrated by the PAD last year.

A clash between PAD protestors and police in October last year, left 443 injured and two protestors dead.

"To date, there has been no independent and impartial investigation into politically motivated violence and human rights abuses related to the PAD protests," Human Rights Watch noted in a statement made available in Bangkok.

While Thai Prime Minister Abhisit Vejjajiva has been widely praised for his handling the UDD-led violence on Monday and Tuesday, there have been calls for him to address some of the protestors' demands for a more equitable society and justice system.

Abhisit came to power after the Constitution Court disbanded the previous government led by the pro-Thaksin People Power Party (PPP) for election fraud.

His Democrat Party has close ties with the PAD that helped bring the PPP government to its knees.

"The question now is what lessons Mr Abhisit will take from the short-lived rebellion," Thitinan Pongsudhirak, a Thai political scientist said in an analysis published in the Bangkok Post newspaper.

"His call for justice for all consistently fails to address the legal infractions of the yellow-shirted protestors of last year. His sense of justice apparently starts from January 2009 when he took office, but not seemingly before then," Thitinan said. (dpa)