An airstrike by the military on Wednesday killed 10 of its own soldiers and injured seven others, the military said.
President Duterte, who launched a ruthless "war on drugs" after he came to power a year ago, has said that the Marawi fighters were financed by druglords in Mindanao, which has been roiled by banditry and separatist insurgencies for decades.
Defense Secretary Delfin Lorenzana on Thursday confirmed that eight foreign fighters were among the Islamist militants killed by security forces in Marawi City.
"Sometimes mistakes happen. All we can do is make sure it will not happen again", he said.
The AFP was not sold on the idea of a temporary cease-fire because it doubted the sincerity of the otehr side, and feared that the lull would allow the enemy to rest, regroup and find better vantage points to attack government troops.
On 23 May after government forces attempted to arrest Isnilon Hapilon, a militant leader, hundreds of Islamist gunmen rampaged through Marawi, a largely Muslim city of 200,000 in the southern part of Philippines. "We have to be comprehensive", said Ryacudu, a retired general.
Fighting has killed 120 militants, 38 government forces and 20 civilians, according to government records as of Saturday.
Officials say they have no idea how many civilians are being held hostage by the gunmen, but a Catholic priest, the Rev.
Numerous officials from the Philippines and elsewhere in the region have expressed concern that ISIS members could travel from the Middle East to Southeast Asia, either under the guise of local fighters returning home, or trainers sent to provide expertise and guidance to the so-called "Brigade of the Migrant" based in the southern Philippines.
"The rebellion in Mindanao, it's not Maute, it's purely ISIS", he said.
He said this was one of the problems that make it hard for his government troops to defeat the terrorists.
Militants flying black Islamic State (IS) group flags rampaged through Marawi almost two weeks ago, triggering clashes with troops and police that have left at least 178 people dead.
Most of the civilians have already fled Marawi but up to 2,000 are believed to be in the city.
Air strikes will not be halted over the incident, Armed Forces of the Philippines (AFP) spokesman Brig.
The group were evacuated after Indonesia's Ministry of Foreign Affairs received security guarantees from the Philippine government.
Philippine President Rodrigo Duterte, a controversial figure who has strained relations with the Philippines' traditional ally, America, and is seeking "realignment with China, is himself a native of Mindanao Island, and has served as the Mayor of Davao City, the island's largest city".
"Continued efforts also are being exerted in our collaboration and coordination with other concerned agencies to ascertain the status of victims whose families continue to ask for assistance on their whereabouts, as well as those of the hostages that are known to us", he added.