MANILA (Reuters) - A bomb attack in the southern Philippines that killed 10 bus passengers, mostly students, and injured 42, was intended to derail a peace deal with Muslim rebels, two army officials said on Wednesday.
The Philippines signed a peace deal in March with its largest Muslim rebel group, the Moro Islamic Liberation Front (MILF), aimed at ending four decades of conflict that killed more than 120,000 people and displaced 2 million.
The rebels agreed to disband their guerrilla army and give up their weapons in exchange for more autonomy for the Muslim-dominated region. A new autonomous government is expected to be set up next year.
A rebel splinter group, the Bangsamoro Islamic Freedom Fighters, was responsible for Tuesday's attack, a senior army commander told Reuters, adding that the rebels responsible recently received training in the use of bombs on the southern island of Mindanao.
"They want to undermine the peace process," said the commander, who accused the rebels of opposing the legal framework for autonomy, the Bangsamoro Basic Law.
"This is an act of terrorism," added the commander, who declined to be identified because he was not authorized to speak to the media.
Another army official said the BIFF opposed the government's pact with its rivals. "They don't want the peace process to succeed," said the officer, who also sought anonymity as he was not allowed to speak publicly.
The rebels used an 81-mm mortar, remotely detonated by a mobile phone, the senior commander said, saying the technique was one favored by a student of Abdul Basit Usman, for whom the U.S. State Department has offered a bounty of $1 million.
A spokesman for the Bangsamoro Islamic Freedom Fighters dismissed the army statement as a fabrication intended to malign it. "Bombing civilians would not benefit us," said Abu Misri Mama.
Extortion has not been ruled out as a motive for Tuesday's crime, because the bus company had faced threats for refusing to pay "taxes" to the rebels, said Lieutenant-General Aurelio Baladad, the military commander in the eastern part of Mindanao.
"The al Khobar extortion gang has bombed several buses for refusing to heed their demand," he added.
Reporting by Manuel Mogato; Editing by Clarence Fernandez