The New People's Army (NPA) attack late Sunday near Tubungan town on Panay island came amid government efforts to shore up grain stockpiles through imports. No casualties were reported in the the raid.

Fifteen NPA gunmen forced their way into the compound owned by local rice dealer Maximo Tamisen and poured petrol on two parked trucks, which they then set on fire, said Chief Inspector Edencio Gregorio, the municipal police chief.

The authorities did not say if any grain stocks were destroyed.

Military spokesman Lieutenant-Colonel Jose Torres described the attack as an "extortion-related act by the bandits." The military says the 5,200-member NPA, now in its 39th year of insurgency, funds its operations mainly through extortion of local businesses.

A day earlier the leadership of the NPA's mother organization the Communist Party of the Philippines declared that the Maoist rebels would attack more mines and other rural businesses to take advantage of soldiers pulling back into the cities to control street protests against President Gloria Arroyo.

Defense Secretary Gilbert Teodoro on Monday denounced the threat saying it "borders on terrorism."

"It's quite easy, unfortunately, to do damage to any establishment," he told reporters.

"We have to really guard against such eventualities so at this point in time given that kind of a statement by the NPA, we enjoin vigilance on the part of business establishments to be more security-conscious and aware of their surroundings."