The strike that killed the Philippine soldiers was one of two launched during that particular operation. Up to 2,000 civilians are believed to have been trapped for two weeks in districts held by the militants, the government says.
More than 3,000 soldiers, marines and air force personnel are involved in the fighting, backed by more than 30 assault aircraft, military officials said.
Padilla said that 1,467 civilians had been rescued so far, and that the 500-600 still trapped were low on food and water.
The violence in the city erupted on May 23 after security forces raided on the suspected house of Isnilon Hapilon, a commander of the Abu Sayyaf group and leader of a branch of self-claimed Islamic State (IS) in the Philippines. But officials have long warned that the poverty, lawlessness and porous borders of Mindanao's predominantly Muslim areas mean it could become a base for radicals from Southeast Asia and beyond, especially as ISIL fighters are driven out of Iraq and Syria. Mindanao has already seen Islamist and communist insurgencies and other separatist movements.
In the meantime, the Defense chief said they could not confirm if there were more foreign fighters killed or fighting along with the local militants.
Defense Secretary Delfin Lorenzana said Jihadists from other countries joined the ISIS-linked Maute group that laid siege in the southern Philippines city.
The Philippine SunStar reports that the former mayor of Marawi City, Sultan Fahad Salic, is denying allegations that he provided support to the ISIS-allied Maute terror group when it attacked the city, insisting that some of his own family members are now trapped in the city.
"A group of our military army men were hit by our own airstrikes", Lorenzana said in a text message, according to The New York Times.More news: Harman edges clear, Thomas dazzles in US Open blitz
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A fire blazed in one building moments after a plane dropped its payload.
He said there was no indication they would surrender or flee, and could not say when the military operation would finish as fears over civilian casualties mounted.
The Commission on Human Rights is also "enjoined" to "zealously exercise" its mandate of ensuring the protection of constitutional and human rights of all citizens while martial law is still in force. Restituto Padilla told CNN Philippines. However, the agreement failed to bring lasting peace in Mindanao.
This comes a day after 10 soldiers were killed, and seven were wounded by a misfired bomb on Wednesday.
Lucman said that after running out of supplies at his home, they had to make a daring escape through the streets, dodging bombings and snipers.
In a speech before the troops in Zamboanga Sibugay in the southern Philippines, Duterte said the fight to crush the terror groups "will just take longer" because, unlike the militants, the government is concerned about the civilians who might be caught in the crossfire.
In the same briefing yesterday, Mr. Lorenzana expressed confidence the military will meet its self-imposed deadline today, June 2, to end the conflict in Marawi. "We need to check his statement thoroughly first", Padilla said. "As to ammunition, as we have mentioned before, this rebellious activity turns out to have been well-planned, and adequate preparations had been made", he said on observation that the terrorists seemed to be not running out of ammunition.
But small hardline groups, including the Maute and Abu Sayyaf, have refused to negotiate and sought to united behind IS.