MANILA - Terrorist snipers were captured on camera firing at state troops from atop a mosque in Marawi City Thursday, boosting reports that the extremists have been using the place of worship as camp.

ABS-CBN footage showed snipers from the Maute group perched on the mosque and opening fire on soldiers as plumes of dark smoke billowed in the background.

Gunshots can be heard clattering as security forces fired back.

Thousands of state troops have been battling Islamic State-linked terrorists Marawi since May 23. They have confined the crisis to less than a square kilometer within the lakeside town.

The fighting however intensified anew on Wednesday night as soldiers engaged the rebels in close quarter battle.

ABS-CBN night vision cameras captured the exchange of gunfire that lasted up to the late hours, during which fires broke out and thick smoke engulfed the city.

Military tanks were also seen moving around the old capitol under enemy fire.

As of Wednesday, the battle for Marawi has killed some 700 people, including 539 terrorists and 122 state troops.

In the last 10 days, authorities have recovered 3 cadavers, including that of a suspected terrorist and a member of the Philippine Marines.

"They are already in an advance state of decomposition. They were transported to Iligan City to undergo post mortem examination," said Zia Alonto Adiong, spokesman of the Provincial Crisis Management Committee.

The military and 39 local officials on Thursday discussed reports that some wounded Maute fighters have already escaped from Marawi via Lake Lanao.

The officials also tackled reports that terrorist reinforcements have been trying to get inside Marawi or create a diversion by attacking other towns in Lanao del Sur.

"Kailangan i-counter 'yung growing number of threat sa localities. We also need to secure perimeters of province because there are reports reinforcement are trying to get inside," Adiong said.

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