There were no immediate reports of casualties on the military side.
The military said the gunmen were "occupying an advantage position" and the ground commander requested two attack helicopters to "soften enemy resistance," the military said in a statement.
Soldiers backed by two helicopter gunships engaged Janjalani and his men in fierce gun battles Monday at the boundaries of the towns of Talayan, Datu Odin, and North Upi.
Lt. Col. Buenaventura Pascual, Armed Forces spokesman, said troops had been flown to Barangay Tamar in Talayan town to block the escape routes of the retreating terrorists.
"The operation specifically targeting the Abu Sayyaf terrorists has been coordinated with the MILF, who in turn provided valuable information to the pursuing troops," he said.
Eid Kabalu, Moro Islamic Liberation Front (MILF) spokesman, said they had received information from their commanders helping the Army’s 6th Infantry Division locate the fleeing gunmen that five Abu Sayyaf terrorists were killed in the fighting.
"But these Abu Sayyaf fatalities were not the top leaders of the group," he said.
Military officers said inclement weather and rugged terrain have slowed down troops pursuing the retreating Abu Sayyaf band.
Abu Sayyaf fighters were first reported to have landed at Palimbang, a coastal town in Sultan Kudarat province some two years ago and have since spread to isolated towns in Maguindanao.
Troops started hunting down the Abu Sayyaf band more than a week ago, following a tip from the MILF.
Last year, Air Force planes bombed the hideout of the Abu Sayyaf at the Liguasan Marsh, a 220,000-hectare delta at the border of Maguindanao, North Cotabato and Sultan Kudarat province.
More than a dozen Tausug-speaking gunmen were killed in the airstrikes, but their leaders, Isnilon Hapilon and Janjalani, survived unscathed and reportedly sought refuge in the mountains of Maguindanao. — With Jaime Laude, AFP