Despite what authorities claim as gradual progressing in clearing Marawi City of the ISIS-linked Maute Group, 13 Marines were killed in fighting, a military spokesman said Saturday.

Thirty to 40 Maute gunmen were posted at high-rise mosques and homemade bombs were set up for the members of the Marine 7 th Landing Team at Lilod Madaya which conducted house-to-house clearing operations.

"They are using the mosques as their safe haven. Yesterday, our Marines conducted house-to-house clearing operation and they have encountered the Maute," said Lt. Col. Jo-ar Herrera, spokesman of the 1 st Infantry Division, told reporters in Marawi City.

"They have optimized the mosque and human shields in the conduct of their atrocities. We were saddened in the result that we lost 13 Marines. We are still waiting for the reports of wounded in action," he added.

"They have in place several homemade bombs. That's why we have intense firefight yesterday ," he added.

Soldiers and policemen killed during the near three-week fighting have reached 58.

The 13 Marines killed is the highest in a day since 10 soldiers died due to “friendly fire”.

This came as the US Embassy said “US special operations forces are assisting the AFP with ongoing operations in Marawi through support that helps AFP commanders on the ground in their fight against the Maute and ASG ( Abu Sayyaf Group) militants.”:

Presidential Spokesperson Ernesto Abella told government radio on Saturday “compounding elements” in the military’s quest to clear Marawi City are “using civilians as human shields and utilizing madrasah or mosques as staging areas or safe havens.

Abella, quoting Defense Secretary Delfin Lorenzana, that “holes have been found connecting buildings.”

Hererra said the military will continue to use air strikes “to soften the enemies’ positions.” He pointed out a machine-gun nest which must be taken down. DMS