Snipers and improvised explosive devices positioned by the Maute group in various areas in Marawi City have hampered the advance of security forces, the military said.
"It's going to be a difficult and challenging task on account of [the] reported presence of snipers and improvised explosive devices that were laid on the roads," said Armed Forces of the Philippines (AFP) spokesperson Col. Edgard Arevalo in a press conference on Wednesday.
"Some of them are establishing footholds on tall structures, some of them are situated on top of these structures, establishing sniper positions, so we are going to move very cautiously, taking to account also the safety of the civilians in the area," he added.
Arevalo also cited the evacuation of Marawi residents as one of the reasons why there was a "delay" in the movement of troops.
"Isa rin sa nagpabagal sa pagpasok ng forces kanina ay ang pag-evacuate ng mga residente ng Marawi. Ito ay nag-create ng congestion ng traffic kaya nagkaroon ng bahagyang delay sa ating movement or moving in of personnel," Arevalo said.
Civilians have started to flee to Iligan City, Saguiaran in Lanao del Sur, and other nearby areas following the atrocities in Marawi City.
Guidelines under martial law
The AFP has also drafted the guidelines for operating units following President Rodrigo Duterte's declaration of martial law in Mindanao.
"We are yet to finalize this in the sense that we are yet to receive a final directive or instruction from the President," Arevalo said.
"Ito ay naglalaman ng mga instructions ng mga pamamaraan kung paano gagampanan ng mga sundalo on the ground ang kanilang tungkulin alinsunod sa ipinapatupad ng itinatadhana ng martial law," he said.
"Kasama na rito kung ano ang dapat nilang maging conduct sa mga checkpoint, paano natin ite-treat ang mga tao na darakpin, kung paano natin ipo-proseso at pangangalagaan ang kanilang karapatan sa ilalim ng umiiral na batas," he added.
Duterte declared martial law in the entire region of Mindanao, noting the projected arrival of ISIS in the country and the open defiance shown by lawless armed groups in Marawi City as his "compelling reason" for doing so.
Arevalo, meanwhile, reiterated that the situation in Marawi City is already under control.
"Na-contain na natin ang insidente. Naprevent natin ang posibleng pagescalate pa nito at nagawa natin ang ating plano na mapigilan kung may reinforcement pa o sympathizers pa sila," he said. — BM, GMA News