The military said 11 soldiers sustained minor wounds.
"The bomb fell in an area proximate to a building where some of our men were staying and the ensuing blast caused part of that building to collapse and the debris that fell from the part of the collapsed structure fell on our men causing the death of two and injuries to 11 others", Padilla said.
Defense Secretary Delfin Lorenzana had admitted that the jets that launched the air raid ran out of precision guided munitions, forcing the pilots to use ordinary bombs.
"The FA50 will momentarily be pulled out from employment as close air aircraft until the investigation has been conducted... to look closely at what caused the failure of one of the bombs".
"We are saddened by this unfortunate incident and a team has been created to investigate the circumstances that led to this tragedy", he added.
"But they carry weapons and are involved in the fighting, then it is hard to do more", he added.
The Defense chief described the urban warfare in Marawi City as similar to the Middle East offensives in Mosul, Fallujah and Raqqa. "I need about 15 more days", Duterte said at the 10th listing anniversary of Phoenix Petroleum Philippines Inc.at the Philippine Stock Exchange in Makati City.
They then cited several biblical passages on love of God and neighbor before urging action in showing solidarity with those who have fled Marawi and those who have been taken hostage.
Before the latest report came in, Arevalo said the number of casualty in the ongoing Marawi conflict has reached 379 extremists killed, 89 security forces and 39 civilians.
"Children, as well as hostages are being employed in the firefight".
The prelates also wondered whether martial law across the southern part of the country would ensure the return of peace.
Earlier the military said civilians had been forced to help the militants by carrying supplies and ammunition, caring for the wounded and helping them loot the city, much of which has been destroyed in the fighting and air strikes.
"[The assessment] is now being finished".
Aside from going after the Maute terrorists, the military is still clearing more or less 600 buildings in Marawi City. They also have over 600 buildings to clear.
Even President Rodrigo Duterte, in public speeches, has said he is angry because the people of the city allowed the Maute terror group to set up base in the city and stock up on weapons and munitions.