BY PATRICK FALBY

Thai authorities have chosen "brute force" over conventional crowd control tactics to contain protests, but may be wary of launching a major crackdown for fear of igniting wider unrest, experts said.

Scenes of deadly urban warfare have erupted on the fringes of the group's sprawling encampment in the heart of Bangkok after the army moved in on Thursday to seal off the area after peace negotiations broke down.

The army has warned it will clear the main rally site in an upscale commercial district unless protesters disperse, but has given no timetable for the move and has been mired in what many see as badly planned street battles.

"I do not see a well thought out, systematically implemented containment operation unfolding right now," Anthony Davis, an analyst for Jane's Defence Weekly, said.

"What I see is fits and starts and stops. I don't know whether it's a lack of political will or it's a failure of tactical nerve." At least 31 people have been killed and nearly 230 wounded Bangkok since Friday, after Thai Prime Minister Abhisit Vejjajiva last week shelved a plan to hold early elections because the protesters refused to end the rally.

Live fire zones

All of the fatalities have been civilians. The latest clashes started when the army initiated a lockdown at the rally site, cutting telephone and electricity services, setting up checkpoints on roads into the area and deploying snipers in "live fire zones."

Experts say there appear to be factions within the security forces supporting the Reds and a series of military operations have been bungled, including a failed attempt to arrest protest leaders who fled a hotel.

"Unable to trust its forces for a commando raid or a thorough nonviolent removal of demonstrators, the military has turned to brute force, which is actually easier to apply than sophisticated crowd control," wrote Joshua Kurlantzick, fellow for Southeast Asia at the Council on Foreign Relations.

Even so, analysts said, the government appears to be worried about the potential repercussions of ongoing military operations, which have triggered international alarm and calls for both sides to show restraint.

"No matter how violent the Reds have been in the past week, the government does not have a blank cheque to unleash security forces upon them," said Sunai Phasuk, an analyst at Human Rights Watch.

"The government is sensitive to public opinion." A military operation on April 10 to clear an area of the city of protesters left 25 people dead and more than 800 injured. The army suffered a humiliating retreat and suffered heavy casualties on its own side.

The rallies, which began in mid-March, have been inspired by a new political awareness among Thailand's rural poor, but have found increasing support among others displeased with Thailand's elites.

Capital in danger

Authorities are likely worried that clearing Reds from the capital would spark violent uprisings by members of the movement across northern Thailand, said Thitinan Pongsudhirak, a political scientist at Chulalongkorn University.

"The military has full authority from the government, but not a full hand because of the potential for spontaneous uprisings elsewhere," Thitinan said.

Members of the military may also be afraid that a violent crackdown could bring personal repercussions, he added.

"If there's a backlash against the military for killing hundreds of people in a major crackdown there would have to be some answers," he said.

However, the military has already faced criticism for its tactics.

The designation of "live fire zones" by troops has put them on a "slippery slope" towards serious human rights abuses, Human Rights Watch said on Sunday.

But while troops have set up a cordon around the 4km Red zone, they are being distracted by well-organised Reds around them, said Davis at Jane's Defence Weekly.

"There is a danger that the containers are being contained," he told AFP.

"This is not being done in a manner that sends an unambiguous message to protesters both inside and outside the Red zone saying 'look, this is game over, we're being serious'," he added.

Agence France-Presse