MANILA, Philippines (AP) -- A key supporter of disgraced ex-President Joseph Estrada was arrested Monday and accused of supporting a failed military mutiny over the weekend, while the current Philippine leader ordered an independent probe into the causes of the uprising by junior officers.
Police have alleged that several cronies of Estrada, who was ousted by popular protest in 2001 and is standing trial on corruption charges, aided and fomented Sunday's rebellion.
Nearly 300 mutinous troops who seized a Manila shopping and apartment complex demanding the government resign gave up and retreated peacefully after some 19 hours.
Estrada, who has been in police custody for more than two years, insisted that he had nothing to do with Sunday's drama. "Neither I nor my supporters has a role in this whole thing, and personally, I have nothing to gain from this incident," he said.
President Gloria Macapagal Arroyo vowed Monday to punish the plotters and ordered an investigation into what caused the uprising that shook her presidency.
In a state of the nation address, Arroyo assured the country that she remains in control. The mutineers said they were protesting alleged corruption and misconduct within the military.
"I am constituting an independent commission to investigate the roots of the mutiny and the provocation that inspired it," she told the Congress, which responded with a standing ovation.
"Such actions are deplorable and will be met with the full force of law," she added.
Arroyo traveled to Congress aboard a helicopter and about 3,000 police officers and sharpshooters deployed outside the Congress building for her speech on Monday.
Outside, thousands of protesters called for her resignation, saying Arroyo had failed to give land to poor farmers, control graft and ease poverty.
"The people's call for Arroyo's resignation will continue to escalate, especially after the mutiny by young officers and soldiers," labor leader Elmer Labog said.
Protesters also burned a 12-foot effigy of Arroyo with moving legs, symbolizing the president on the run.
The Philippines has had about eight military uprisings and coup attempts since the "people power" ouster of dictator Ferdinand Marcos in 1986.
The force of Arroyo's words immediately fueled speculation that she might reverse an earlier promise not to stand in next year's presidential election.
Arroyo did not mention her political plans but pledged action to solve critical problems including terrorism, drugs, corruption, separatism and the struggling economy.
Police announced earlier Monday that they were using emergency powers granted by Arroyo to quell the mutiny to detain some of Estrada's associates. The powers allow arrests without warrants.
The first to be nabbed was Ramon Cardenas, a member of Estrada's Cabinet. Officials filed a complaint against him late Monday before the justice department in connection with his alleged role in the uprising. A lawyer for Cardenas, Abraham Expejo, said his client was innocent.
Officers said he owned a "safe house" for the rebel troops -- stacked with assault rifles, ammunition and the same red armbands used by the soldiers who seized an apartment and ritzy shopping complex in downtown Manila.
Police are trying to gather evidence against Sen. Gregorio "Gringo" Honasan, also suspected of providing help to the mutineers, said police official Eduardo Matillano. Honasan, a former army colonel who led seven coup attempts in the 1980s, has not been charged and has strongly denied the accusation.
Arroyo also promised to reform the police force, branded as corrupt and inept following the July 14 escape of three terror suspects thought to have bribed their way out of its main Manila headquarters.
Arroyo, however, failed to outline a widely expected change of senior police commanders -- something that had been included in a draft of her speech supplied to reporters. There was no explanation about the omission.
Financial markets plunged Monday in response to the failed mutiny, but major shares bottomed out early and contained their losses at 2.1 percent as traders focused on the quick, peaceful resolution to the crisis.
Five junior officers, who organized the uprising, were being questioned under guard, said army spokesman Lt. Col. Joselito Kakilala. The other mutinous troops were confined to their barracks.
The mutineers demanded the resignation of Arroyo, but backed down during talks with government negotiators and after Arroyo threatened to crush the rebellion with tanks and sharpshooters.
The renegades wired the apartment and shopping complex -- home to some of the city's richest citizens, foreign businesspeople and diplomats -- with explosives and booby traps.
The renegades complained of corruption and misconduct in the upper ranks of the military and government and complained that Muslim and communist rebels were buying weapons and ammunition from the military.