MANILA, May 5 (Reuters) - Hundreds of Maoist-led rebels ambushed a Philippine army convoy on the troubled southern island of Mindanao on Monday, killing three soldiers and wounding 18 others, officials said.
Major Lyndon Paniza, a battalion commander in North Cotabato province, said a large formation of communist New People's Army (NPA) attacked a convoy of army trucks returning to base in one of the region's rice-producing areas.
"Our troops were returning home early today when one of our trucks struck a landmine," Paniza told reporters, adding the soldiers also came under heavy gunfire from rebels on both sides of the road.
"Our outnumbered troops fought back for several minutes until reinforcements came to push back the rebels. We're not sure how many we got from their side, but they must have suffered heavy casualties, too."
Paniza said three soldiers were killed in the initial burst of gunfire and six were taken to a nearby private hospital.
But an official from the hospital told reporters at least 18 soldiers were being treated for gunshot and shrapnel wounds.
"A couple of them were actually in very critical condition due to bullet wounds in the head," Fe Mendoza of the Arakan Valley hospital told reporters.
"They have to be transferred soon to better equipped medical facilities."
Active in 69 of 81 provinces across the Philippines, the NPA rebels have been fighting for nearly 40 years to set up a Maoist state in the Southeast Asian country. The conflict has killed more than 40,000 people.
The rebels' political arm, the National Democratic Front (NDF), has been in on-and-off peace negotiations with government, but walked out in 2004 when Manila did not help it get removed from terrorism blacklists in Western Europe and the United States.
Since the start of 2008, the rebels have stepped up attacks to boost morale and raise funds through extortion, hitting mine sites, plantations and telecommunications towers on Mindanao. (Reporting by Manny Mogato; Editing by Raju Gopalakrishnan and Jerry Norton)