The two leaders were named as Isnilon Hapilon, who was declared the terror group's emir for Southeast Asia, and Omar Maute, a leader of a local militant group that had pledged allegiance to ISIS.
The pair were killed, along with seven other militants, while attempting to exit a building at street level during a four-hour firefight, Gen. Eduardo Ano of the Philippines Armed Forces said at a news conference. Maute was shot in the head by a sniper.
Their bodies were positively identified by a former hostage, Ano said. They will be buried in accordance with Islamic rites in an undisclosed location.
"It will be just a matter of days before it can finally be declared that Marawi has been liberated from the clutches of terrorists," he said.
More than 800 militants and 162 government security forces have been killed in the nearly 150 days of fighting, and about 1,700 hostages have been rescued, including 20 on Monday, said Ano.
The deaths of both Hapilon and Maute will likely hasten the retreat of ISIS-affiliated militants from Marawi, according to Richard Heydarian, a security analyst and author of the new book "The Rise of Duterte: A Populist Revolt against Elite Democracy."
"The political and military leadership of the ISIS movement (in the Philippines) has essentially been neutralized," Heydarian told CNN.# head 
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