ZAMBOANGA CITY: Security forces fighting local Islamic State (IS) militants in war-ravaged Marawi City continue to advance to the main battle area and troops go on house-to-house searches scouring for booby traps and improvised explosives that have already killed scores of soldiers.

Security officials said militants have planted explosives in houses and buildings and structures they occupied making it extremely difficult for troops to accomplish their mission – to kill the enemy, rescue civilian hostages and liberate Marawi, the capital of Lanao del Sur.