MARAWI, Philippines (Reuters) - The Philippine military said on Monday it was close to retaking a southern city held for a seventh day by Islamist militants, as helicopters unleashed more rockets on positions held by the rebels aligned with Islamic State.
The occupation of Marawi city by the Maute, a group hardly heard of a year ago, has become the biggest security challenge of Rodrigo Duterte's 11-month presidency, with gunmen resisting air and ground assaults and controlling central parts of a city of 200,000 people.
The military said the rebels may be getting help from "sympathetic elements" and fighters they had freed from jail during the rampage that started on Tuesday and caught the military by surprise.
"Our ground commanders have assured that the end is almost there," military spokesman Restituto Padilla told reporters. "We're trying to isolate all these pockets of resistance."
More than 100 people have been killed, most of them militants, according to the military, and most of the city's residents have fled.
The military said the Maute group was still present in nine of the city's 96 barangays, or communities.
The Maute's ability to fight off the military for so long will add to fears that Islamic State's radical ideology is spreading in the southern Philippines and it could become a haven for militants from Southeast Asia and beyond. Malaysians and Indonesians were among the rebels killed.
The government believes the Maute carried out their assault before the Muslim holy month of Ramadan to capture the attention of Islamic State and earn recognition as a regional affiliate.
According to witnesses, men with black headbands typical of Islamic State have been seen on city streets in recent days. A photograph taken by a resident shows 10 men carrying assault rifles and dressed entirely in black.
A Reuters photographer saw an Islamic State flag in an oil drum in an abandoned street on Monday, where chickens roamed in front of damaged shops and homes.
Some troops tried to eliminate Maute snipers on Monday as others guarded deserted streets, taken back block by block.
Helicopters circled the lakeside city and smoke poured out of some buildings. Artillery explosions echoed.
Nearby Iligan City was in lockdown over fears that Maute fighters had sneaked out of Marawi by blending in with civilians.
"We don't want what's happening in Marawi to spill over in Iligan," said Colonel Alex Aduca, chief of the Fourth Mechanized Infantry Battalion.
Sixty-one militants, 20 members of the security forces and 19 civilians have been killed since Tuesday, when Maute rebels went on the rampage after a botched military operation to arrest Isnilon Hapilon, who the government believes is a point man for Islamic State in the Philippines.
Though most people have left, thousands are stranded, worried they could be intercepted by militants if they tried to flee.
CNN Philippines reported that 10 people taken hostage while fleeing Marawi had escaped their Maute captors during an air strike on Monday and were in safe hands. The report said they witnessed the beheading of another hostage a day earlier.
A video of several of the men was circulated online on Monday, showing them begging Duterte to stop military operations, otherwise they would be decapitated.
Reuters could not verify the authenticity of the video or the accounts given in the news report.
The military has warned that atrocities may have been committed by the Maute. The bodies of what appeared to be eight executed civilians were found in a ravine outside Marawi on Sunday, some with their hand bound.
Zia Alonto Adiong, a politician involved in evacuation efforts, said civilians stuck in Marawi wanted air strikes to stop.
"The anticipation of death is worse than death itself," he told news channel ANC. "We appeal to our military forces to do a different approach."
Army spokesman, Colonal Edgard Arevalo, said "surgical strikes" were taken on "known and verified enemy positions".
Duterte imposed martial law last week on Mindanao, an island of 22 million people where both Marawi and Iligan are located, to quell the unrest and try to tackle radicalism.
He made an unconventional offer on Saturday to Muslim separatists and communist rebels to become "soldiers of the Republic" and join his fight against extremists.
Additional reporting by Erik de Castro in MARAWI and Neil Jerome Morales, Karen Lema and Manuel Mogato in MANILA; Writing by Martin Petty; Editing by Robert Birsel