MANILA, Philippines – The military warned of more bombings in Central Mindanao, which it said was part of the “grand plan” of Moro rebels to sow “terror” and distract the military from its pursuit of rebel commanders.

The explosion near a church in Cotabato City on Sunday that left five people killed and scores others wounded was “connected” to explosions in Koronadal City and Datu Piang town in Maguindanao province, Armed Forces spokesman Lieutenant Colonel Romeo Brawner Jr. said.

Citing a report from the Army’s 6th Infantry Division, which is based in the region, Brawner said the recent bombings were “test missions” of new recruits to the Moro Islamic Liberation Front’s urban squad.

To thwart the plan, Brawner said the military “enhanced” security in Central Mindanao, especially in bus terminals, malls, and churches.

“There is a big possibility that there will be more bombings,” Brawner told reporters, adding that the military has recovered 59 bombs.

“Their objective, aside from sowing terror in the area, on the tactical level, to divert our troops so that we could not pour all our resources running after Ameril Ombra Kato,” he said.

The military is running after MILF commanders Kato, Abdurahman Macapaar, and Aleem Pangalian, the alleged brains of attacks in North Cotabato and Lanao del Norte in August 2008.

The attacks came after government and MILF peace negotiators failed to sign a key agreement on territory, which would have expanded the Autonomous Region in Muslim Mindanao (ARMM). The Supreme Court later declared the botched agreement unconstitutional.

The military is also investigating the possible involvement of the Jemaah Islamiyah (JI), the Southeast Asian arm of Osama bin Laden’s al Qaeda network, in Sunday’s explosion, said Major Randolph Cabangbang, spokesman of the Eastern Mindanao Command (Eastmincom) of the Armed Forces.

Cabangbang told reporters a number of JI militants were "here in the country."

Known JI members Dulmatin, Umar Patek, and Zulkifli bin Hir are thought to be operating in the southern Philippines, he said, but added that there was no proof yet of their involvement in the attack.

"There's an ongoing operation to capture those terrorists. We have a directive from Manila to augment our bomb experts and to provide additional bomb-sniffing dogs," he added.

The Philippine military believe JI militants in the Philippines have given bomb-making training to another Islamic separatist group, the Moro Islamic Liberation Front (MILF).

The military alleges the MILF is behind some previous bombings of Christian targets in the southern Philippines.

But the MILF denied any involvement in Sunday's bombing.

"We are not responsible for the bombing," MILF spokesman Eid Kabalu told reporters. "We even condemn this attack."

United States military advisers are helping with the investigation, Cabangbang added.

Small numbers of US military advisers are deployed in the southern Philippines to train Filipino troops fighting Islamic militants in a region wracked by decades of Muslim separatist rebellion.

"US forces are helping their counterparts by providing support. They have their own bomb experts and they would share analysis with each other," Cabangbang told reporters.

"(The Americans) are not directly involved in the hunt against the bombers. They would analyze if foreign terrorists have (a) hand in the attack."

Meanwhile, Army 6th Infantry Division spokesman, Lieutenant Colonel Jonathan Ponce, said one man was being questioned by police after being picked up by military agents in the city immediately following the blast.

"The suspect was trapped because he’s not familiar (with) the city," Ponce said.