Arroyo issued a proclamation and general order for the military and police "to suppress and quell the rebellion" under special powers given her by the constitution, presidential spokesman Ignacio Bunye told a news conference.

Troops and police are ordered to "immediately carry out the necessary and appropriate actions and measures to suppress and quell the rebellion with due regard to constitutional rights," he added.

Bunye read out the orders less than four hours before the end of an ultimatum Arroyo set for the rebels to stand down or face military assault.

Bunye said a Filipino senator was negotiating with the rebels for a peaceful end to the standoff, but gave no details.

Arroyo said these "misguided elements are being supported, abetted and aided by known and unknown leaders, conspirators and plotters in the government service and outside the government." She gave no details.

Her predecessor Joseph Estrada and opposition Senator Gregorio Honasan earlier rejected government allegations that they were behind the latest military uprising.

WAR.WIRE