RPT-Thai protesters defy PM ultimatum to leave

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BANGKOK, Aug 28 (Reuters) - A deadline set by Thai Prime Minister Samak Sundaravej for tens of thousands of protesters to leave his official compound passed on Thursday as the group's leaders vowed to stay until his government fell.

Samak ordered thousands of riot police to break up the demonstration at Government House by Wednesday but police were powerless to exercise arrest warrants for the nine protest leaders overnight due to the sheer weight of numbers.

The People's Alliance for Democracy (PAD) crowd, maybe as many as 40,000 strong and including large numbers of middle-aged women, also defied a court order to leave to compound.

Makeshift barricades of car tyres, razor wire and steel crash barriers on roads leading to the PM's office mean moving the protesters will be a major task.

As the sun rose on Thursday morning, police had taken no action despite having arrest warrants for nine PAD leaders on charges of inciting unrest and trying to overthrow the government, a crime punishable by up to 15 years in prison.

Dozens of police trucks were parked on streets nearby and police doctors and ambulances were on stand-by at police headquarters, Thai television reports said.

The PAD accuses the government elected in December of being an illegitimate proxy of Prime Minister Thaksin Shinawatra, who was booted out by the army in a 2006 coup.

It also proclaims itself to be a defender of revered King Bhumibol Adulyadej against a supposed Thaksin plan to turn Thailand into a republic -- a charge vehemently denied by both Thaksin, now in exile in London, and the government. (Reporting by Pracha Hariraksapitak; Writing by Nopporn Wong-Anan; Editing by Ed Cropley and Valerie Lee)