Government troops had entered three neighborhoods from which the pro-Islamic State militant group (ISIS) fighters who seized the town on May 23 had pulled back, said Major General Carlito Galvez, head of the military command in the region.
"We saw food, IEDs, mobility assets. Considering we have paralyzed logistics capability, we are looking at the possibility that the end will be near," he told a news conference in Marawi City, referring to improvised explosive devices, or bombs.
The military believed "more or less 100" civilians were still being held hostage by the militants, he said.
Task force head Brigadier General Rolly Bautista told reporters that a Catholic priest who was taken hostage with about a dozen of his parishioners on the first day of the siege, was still alive. He said this was information passed back through emissaries.
The battle for Marawi has raised concern that ISIS, on a back foot in Syria and Iraq, is building a regional base on the Philippine island of Mindanao that could pose a threat to neighboring Indonesia, Malaysia and Singapore too.
Officials have said that, among the several hundred militants who seized the town, there were about 40 foreigners from Indonesia and Malaysia but also fighters from India, Saudi Arabia, Morocco and Chechnya.
The strike on Marawi City suggested to many that pro-Islamic State factions wanted to establish it as a Southeast Asian "wilayat" – or governorate - for the radical group, a view reinforced by video footage the military found last week showing the fighters plotting to cut the town off completely.