Thai authorities say they have restored order in most of Bangkok a day after launching a deadly operation to clear thousands of opposition Red Shirt activists from a protest site in the capital.  Security forces fired warning shots Thursday in parts of the capital as they searched for militants who resisted Wednesday's government raid on the Red Shirts' encampment.

Officials say the number of people killed in the raid has risen to 15 with another 100 people wounded. The dead include six people whose bodies were recovered from a Buddhist temple within the protest zone.

Militants responded to the raid by setting fire to at least 35 Bangkok buildings, leaving many in ruins, including the Center World mall, one of the region's biggest. Some buildings were still smoldering Thursday as firefighters tried to put out the flames.

City workers also started to clean up the area the Red Shirts had occupied in Bangkok's commercial hub for more than two months. The protesters had demanded early elections to replace a government they deemed illegitimate and elitist. Most of the protesters are rural poor and working class activists who support deposed former Prime Minister Thaksin Shinawatra.

Thai government spokesman Panitan Wattanayagorn expressed understanding Thursday for the frustrations of the Red Shirts. But he also said arson attacks and looting carried out by some protesters were criminal acts that amount to organized terrorism.

Three Red Shirt leaders turned themselves in to police Thursday, raising the number in police custody to eight. One of the three who surrendered, Veera Musikapong, appealed for calm and told supporters that democracy can not be built on revenge and anger.

Thai officials said they were transferring the Red Shirt leaders to a military camp south of Bangkok for interrogation. Authorities also extended a nighttime curfew in Bangkok and 23 provinces to Saturday morning. Thailand's unrest spread this week to the northeastern cities of Udon Thani and Khon Kaen, where militants carried out arson attacks on government buildings.

Violence in Bangkok has killed at least 82 people and wounded 1,800 others since the Red Shirts began their demonstrations in March.