Police in the Philippines say they have arrested an aide of former President Joseph Estrada on suspicion of involvement in an uprising by members of the military at the weekend.
Ramon Cardenas is suspected of links with the rebels
Nearly 300 heavily armed soldiers abandoned their posts and seized part of the capital, Manila, on Sunday but surrendered without a shot being fired.
Ramon Cardenas, a former junior minister in the Estrada government, was arrested following a raid on his house which uncovered weapons, ammunition and red arm bands similar to those worn by the renegade soldiers, police said.
The BBC's John McLean in Manila says authorities are trying to find out if the mutiny was part of a bigger plot to destabilise or even overthrow the current president, Gloria Arroyo.
In spite of the crisis, Mrs Arroyo went ahead with a state of the nation address on Monday in which she promised to launch two independent commissions to investigate the roots of the mutiny.
One enquiry will investigate the mutineers' complaints about low pay and corruption among senior officers.
She said there would also be an independent investigation into a bombing in the Muslim south which soldiers accused the government of carrying out to ensure the support of the United
Talks would be held next week in Malaysia with the Moro Islamic Liberation Front (MILF), which has been waging a decades-old separatist
rebellion, she added.
Mrs Arroyo has said both the officers involved and any political backers of the rebellion will be investigated.
However, a prominent opposition politician involved in negotiations to end the rebellion said the soldiers had voiced valid concerns.
"We consider that most of the grievances are legitimate," said Senator Rodolfo Biazon.
The soldiers had barricaded themselves into a shopping and residential complex in the Makati business district for 19 hours before agreeing under threat of force to return to barracks.
They accused the government of corruption and demanded the resignation of Mrs Arroyo and her Defence Minister, Angelo Reyes.
Dr James Putzel, a South East Asia expert at the London School of Economics (LSE), has told the BBC that while the rebellion never really threatened the government, it was nonetheless evidence of malaise in both the military and the country as a whole
'No special treatment'
Mrs Arroyo said the 296 mutineers had neither sought nor would be given "special treatment".
"They will be investigated and their cases will be disposed of in accordance with the articles of war," she said.
Civilians involved in any plot linked to the mutiny, she said, would be prosecuted.
The rebel soldiers returned to barracks after the mutiny ended
Navy Lieutenant Antonio Trillanes, one of the rebel leaders, said before his surrender that the soldiers had been "ready to die" but had ended their actions to prevent needless bloodshed.
Our correspondent says the rebels had clearly given up under threat of force and that they had not won wider support within the army.
After the rebels agreed to surrender, they filed out of the Glorietta complex carrying weapons and boxes of ammunition, to be driven back to barracks.
Explosives set by the rebels were dismantled and reporters saw anti-tank weapons, machine-guns and a rocket launcher being removed from the Glorietta area.