Marawi (Philippines): A Philippine military official says an air force airstrike killed 11 soldiers and wounded seven others in "friendly fire" as government forces struggled to rout the remaining Islamic extremists who laid a siege in a southern city for a week.

Military spokesman Brig. Gen. Restituto Padilla said on Thursday a Marchetti S-211 jet was on a bombing run over militant positions in Marawi city on Wednesday when one bomb hit an army position locked in close-range combat with the extremists.

Padilla says the plane made three successful bombing runs before the wayward bombing happened. He added the military has ordered an investigation.