REUTERS/EPAISIS-affiliated militants have held the Filipino city of Marawi for more than eight days
The Filipino soldiers died after they were hit by friendly fire from a military air strike, which had been targeting the terror group.
The Philippines's defence secretary Delfin Lorenzana said: “A group of our military army men were hit by our own airstrikes... 10 killed [later revised to 11] and 8 wounded.
"Sometimes the fog of war... The coordination was not properly done so we hit our own people."
EPATroops from the Filipino army rescues from the embattled city
He added: "There were two planes flying. The first plane dropped the ordnance accurately, the second went wrong and hit our troops.”
His comments come after the Filipino president, Rodrigo Duterte, declared marital law until the country is safe from the terrorists.
The Philippine armed forces have been using a combination of ground operations by soldiers and helicopters air strikes in a bid to dislodge the Abu Sayyaf Group from its hold on the