MANILA, May 4 (Xinhua) -- Philippine government troops have killed at least nine Abu Sayyaf militants in an airstrike in Sumisip town in the southern Philippine Basilan island province, the military reported on Friday.

The military said the firefight broke out around 2:30 a.m. on Wednesday in a village in Sumisip town, sparking a 30-minute fighting between the troops and some 40 Abu Sayyaf extremists that resulted in the killing of the nine militants.

The military said a certain Furuji Indana led the Abu Sayyaf militants. Indama reportedly replaced slain leader Isnilon Hapilon, the alleged Islamic emir for Southeast Asia who was killed at the height of the Marawi siege last year.

"It was not immediately confirmed if Indama was among the casualties in the airstrike. However, we have confirmed reports on the ground 9 of the Abu Sayyaf were killed in our operation," Basilan Island military commander Brig. Gen. Juvymax Uy said.

Uy said ground troops recovered one dead body of the Abu Sayyaf and three assault rifles from the clash site. He said the government did not incur any casualty.