Philippine military officials say suspected communist guerrillas have killed six policemen and wounded eight others in an ambush in the northern Philippines in the latest flare-up of the decades-old Marxist insurgency.

Army Maj. Gen. Lysander Suerte says about 40 New People's Army rebels detonated a bomb then opened fire on a truckload of policemen in the coastal town of Baggao in Cagayan province Tuesday, sparking an hourlong gunbattle.

Suerte says two assault helicopters were deployed and soldiers and policemen were pursuing the attackers, who burned construction equipment in a nearby farm irrigation project late Monday.

The Marxist insurgency has flared on and off for more than four decades and is one of the longest-running rebellions in Asia.