Mr. Abhisit’s emergency decree reversed a nonconfrontational approach critics said had contributed to the cancellation of the summit meeting on Saturday. At the meeting, in the beach resort of Pattaya, hundreds of protesters broke through a thin line of security officers to enter the hotel complex where the leaders were gathered. Several leaders were evacuated by helicopter.

The meeting was to have included the heads of the 10 members of the Association of Southeast Asian Nations, the leaders of China, Japan and India, the United Nations secretary general and the president of the World Bank. The officials had planned to discuss the global financial crisis.

“Yesterday was a truly shameful day for our country, which had its international reputation destroyed,” The Bangkok Post said in a front-page editorial on Sunday. “It is one thing to refuse to use force; it is another to allow protesters to run riot into the summit venue, blocking access to the hotel and putting foreign leaders at risk.”

Although the protests have slowed traffic in parts of Bangkok, they have not affected daily business or posed a difficulty to tourists. Bangkok’s airports, which were shut by huge protests in November, remained open and were functioning normally. Hotels were open, and foreigners said they did not feel threatened.

“We feel very safe,” said Thibault Quetel, 20, from France, who is studying economics here. “This is a problem between Thais. There hasn’t been any animosity toward foreigners.”

Mr. Thaksin’s supporters, who mostly come from his base in the countryside, represent one side of a deep social and political divide that pits them against the “yellow shirts,” who demonstrated last year against a pro-Thaksin government.

The yellow shirts generally represent the country’s established power centers, including the royalists, the elite and middle class, and the military, who feel threatened by Mr. Thaksin’s attempts to change the country’s balance of power.