MANILA – The military on Wednesday said the number of civilians killed in the ongoing Marawi clash could "significantly increase", as more killings have yet to be verified by the government.

Armed Forces Spokesperson Brigadier General Restituto Padilla said the military got hold of footage showing the terrorists carrying out executions.

He, however, said the death toll arising from these killings was not yet included in the official figure on civilians killed, which currently stands at 27.

"We are not certain on exactly how many civilians [have been killed] because the number you have now, which is 27, may increase significantly once we are able to validate all these information," Padilla said in a news conference in Malacañang.

"There have been a significant number [of slain civilians] seen in the video but again we could not include many of these [to the official death toll] because we have not validated or authenticated [this] information. Until such time, we will remain with those numbers."

Padilla said the terrorists who laid siege to Marawi, a cultural and economic hub located at the heart of Mindanao, took footage of some of their killings supposedly to gain recognition from the Islamic State in Iraq and Syria, with which they pledged allegiance.

"Whatever the objective of the terrorists from inside - either to scare people or to communicate across other members of the country of their extreme and radical ways - has been achieved because of that," he said.

DAY 36

The battle for Marawi entered its 36th day on Wednesday, with intense gunfights and bombing in the heart of the town and black-clad fighters seen from afar running between buildings as explosions rang out.

Marawi is the only city in the Christian-majority Philippines that the government has decreed to be "Islamic", because of its large population of Muslims.

The siege in Marawi began on May 23 when the Maute group, led by brothers Omar and Abdullah, captured parts of the city in an alleged bid to establish an ISIS province in Mindanao. Nearly 400, mostly suspected terrorists, have perished.

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The clashes erupted after government troops attempted to arrest Abu Sayyaf senior leader Isnilon Hapilon in the city. Hapilon, known as ISIS' anointed leader in Southeast Asia, evaded arrest and has reportedly left the city after weeks of fierce clashes.

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Padilla said reports of Hapilon’s departure from Marawi have yet to be verified. He said the military will continue to operate under the assumption that the top terror leader remains holed up in the city.

“If it is true that he already left Marawi City, it shows that he is a coward,” he said.

He added the military is working to fully quell the siege, especially that the second State of the Nation Address of President Rodrigo Duterte is just a month away. He, however, made no commitment that the military can end the siege in a month, citing the challenges in the battle zone.

The clashes prompted Duterte to put the entire Mindanao under martial law, a declaration which is now being opposed before the Supreme Court.

The emergence of groups pledging allegiance to the ISIS has been considered as the biggest security problem to face the year-old Duterte administration.

The rise of pro-ISIS groups in the country has raised alarm in Washington and the Philippines’ neighbors in the region, which fear that the notorious terror group was seeking to establish a new front in Asia amid its successive losses in Iraq and Syria. With Reuters