MANILA, Philippines (AP) -- At least 43 Philippine police commandos were killed in a fierce battle with Muslim guerrillas after launching an assault in which they may have killed one of Southeast Asia's most-wanted terrorists, officials said Monday.
The clash Sunday - the biggest single-day combat loss for the government in recent memory - may have resulted from the commandos' failure to follow the terms of a cease-fire with the guerrillas by notifying them of their presence in the area, a rebel leader said.
Interior Secretary Mar Roxas described the clash as a "misencounter."
A police Special Action Force member remained missing while 11 others were wounded in the fighting in the remote village of Tukanalipao in Maguindanao province, officials said. Seven of the dead were officers.
Roxas called the commandos "fallen heroes" who sacrificed their lives to try to capture Malaysian bombing suspect Zulkifli bin Hir, or Marwan. The top terror suspect may have been killed by the commandos and efforts were underway to confirm that suspicion, he said.
Another top terror suspect, Filipino bomb-maker Abdul Basit Usman, managed to escape, according to Roxas, who flew to the south with the defense secretary and military and police chiefs following the police loss.
The United States has offered up to $5 million for Marwan's capture and $1 million for Usman. Both have been blamed by U.S. and Philippine authorities for deadly bomb attacks and providing bomb-making training to al-Qaida-linked militants in the country's south.
"There is sadness and bitterness because there are more than 40 bodies here," Roxas said at a news conference, where he promised to provide help to the slain commandos' families.
After attacking Marwan, the police commandos came under fire from hard-line Muslim insurgents in the village, and some strayed elsewhere and became entangled in a firefight with insurgents belonging to the Moro Islamic Liberation Front, the main Muslim rebel group, national police Deputy Director General Leonardo Espina said.
The Moro rebels signed a peace deal with the government last March that aims to establish a more powerful and better-funded autonomous region for minority Muslims in the south and end a decades-long rebellion. The conflict has left 150,000 people dead and helped stunt development in the country's poorest regions.
Under the terms of a cease-fire, government forces are required to coordinate their anti-terror assaults and other law enforcement operations with the Moro rebels to prevent accidental fighting. But the police commandos did not notify the rebels before they entered the Muslim rebel stronghold in the dark, Moro rebel leader Mohagher Iqbal said.
"If somebody barges into your house, what will you do?" Iqbal said by telephone.
He said the 11,000-strong Moro group would file a protest over the action of the police commandos, adding that he hoped the incident would not undermine the peace process, a view shared by Philippine officials.
The mayor of the township around the village where the clash occurred, Tahirudin Benzar Ampatuan, said by telephone that village leaders described the battle scene as "gruesome" and said many of the dead were stripped of their uniforms and other belongings, including their assault firearms.
The military had previously announced in 2012 that Marwan had been killed in a U.S.-backed Philippine air strike in southern Sulu province along with another militant, Singaporean Mauwiyah, but police special forces believed otherwise and continued to discreetly hunt him.
Associated Press writer Teresa Cerojano contributed to this report.
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