Washington had offered a USD 1 million award for Usman's capture and prosecution.
Gen Gregorio Pio Catapang said that infighting among Usman's bodyguards led to a firefight yesterday in southern Maguindanao province, near a designated safe area for the Moro Islamic Liberation Front, the largest Muslim rebel group that signed a peace deal with the government last year.
He said Usman and five others were killed in a shootout allegedly with fellow members of his group.
"What we are confirming is Basit Usman is dead," he told reporters, saying the military has physical evidence, including people who saw Usman's body being buried.
A tussle for the bounty may have fueled the infighting, Catapang said, adding that Usman has become distrustful of his men after a series of clashes with the military.
Usman escaped a police commando operation in January that killed one of Southeast Asia's most-wanted terror suspects, Malaysian Zulkifli bin Hir or Marwan, also in Maguindanao.
