National Security Adviser Norberto Gonzales said supporters of opposition leader Fernando Poe were trying to spark civil unrest during Monday's voting aimed at bringing down Arroyo's government.

"The plot consists of a coordinated action plan involving civilian, retired and active military operatives," Gonzales told reporters.

He said the aim was to spark civil unrest similar to rioting by millions of supporters of deposed Joseph Estrada in 2001.

"The objective is, it ends with a takeover," Gonzales said.

The Philippines, which has a long history of coups and military plotting, has been gripped by rumours and unsubstantiated allegations of unrest throughout the election campaign.

In July last year around 300 junior military officers briefly took over a Manila luxury apartment block and demanded Arroyo step down. Many believe politicans associated with Estrada were behind the rebellion.

A spokesman for Poe, Mike Romero, rejected the allegations as "uncalled for and unfair".

The latest independent opinion polls have Arroyo opening up a lead of between four and seven percentage points over Poe.

WAR.WIRE