Troops from the Armys 47th Infantry Battalion and 1st Scout Ranger Company were thrown off from the Mitsubishi Elf truck they were riding after it passed over the improvised land mines.
Armys Task Force Panay spokesman Maj. Lyndon Sollesta said the rebels detonated the land mines before opening fire, triggering the firefight.
An undetermined number of rebels were hit during the ensuing gun battle, Sollesta said.
Initial reports identified eight of the fatalities as Corporals Marlon Pitalyo, Noel Rosbert and Rodelo Pasya; Privates First Class Villamor and one Angeles and Staff Sergeants Paterno Villorente, Ronel Panes and Milquiades Montemayor.
Officials said about 40 NPA guerrillas were involved in the attack against the soldiers, who were returning to base to get supplies for an ongoing operation.
The rebels reportedly used two small "command-detonated" LPG tanks as land mines similar to those found about a month ago in Igbaras town, Sollesta said.
Army spokesman Maj. Bartolome Bacarro added police operatives joined Army troops in hunting down the rebels.
"This is a very unfortunate and this shows the terrorist mind of the NPA," Bacarro said.
He said the land mines were planted to prevent troops from being deployed in rebel-infested areas.
Bacarro said the attackers even attempted to finish off the wounded soldiers and grab their rifles and ammunition.
"Not a single firearm was taken from our soldiers by the rebels as members of the Army, although wounded, are determined to fight these bandits," Bacarro said.
In a separate clash, a policeman was killed and three others wounded, also on Saturday when they pursued a group of NPA rebels who had attacked a cellphone tower in Lucban, Quezon, a military report said.
About 50 NPA guerrillas had disarmed the security guard at the Globe Telecommunications tower in Lucban and then tried but failed to topple the tower with dynamite.
It was the 19th such NPA attack on Globe towers this year, apparently in retaliation for the companys refusal to pay the rebels extortion demands.
In another incident, suspected NPA fighters fired on a residential house in Tanay, also on Saturday, wounding a couple and their young daughter, police said.
The 8,000-strong NPA is the armed wing of the Communist Party of the Philippines (CPP), which has been waging a Maoist rebellion since 1969. Both groups are on the US governments list of foreign terrorist organizations.
Peace talks between Manila and the communists grounded to a halt last year after the rebels demanded to have them removed from the blacklist.
The rebels have vowed to intensify attacks in the hope of further undermining the government. With Cecille Suerte Felipe, AP, AFP