Military, police both failed to do their duty : PM

However, he said his government would not make any personnel changes at this time, although it would try to improve the security system. The country remains confronted with many tough challenges, and now is not the time to apportion blame, he said.

"I feel the policemen and soldiers did not do their jobs to the best of their ability," he said.

Abhisit made the first public statement blaming a flawed security system for the red-shirt protesters breaking through the barriers and storming the meeting, prompting its cancellation and the emergency evacuation of the national leaders attending.

He conceded his government had underestimated the red shirts and thus his initial decision to rely on law enforcement instead of crowd control.

"The delay in crowd control may have boosted the confidence of the red shirts in turning increasingly unruly, which eventually triggered riots in several areas around the capital," he said.

He disclosed he had not yet made up his mind whether to disperse the red shirts at Government House on Tuesday when rally organisers contacted the authorities and volunteered to call off the demonstration.

"At the time, I instructed the soldiers only to maintain pressure on the protesters and had not given a green light for a crackdown," he said.

He said he had been saddened by the incident in which the red shirts attacked his vehicle following the declaration of emergency rule on Sunday.

"The situation has accelerated from bickering to threats to people's lives," he said, admitting security for him and his family had been beefed up.

He voiced concern about yesterday morning's gun attack on yellow-shirt leader Sondhi Limthongkul.

Security for the prime minister has been upgraded to the maximum level. The Armed Forces Security Centre is now completely in charge of providing a VIP-protection team consisting of Army officers.

Abhisit's motorcade will be organised by the military instead of the police.