Civilians who have escaped the besieged city of Marawi in the southern Philippines say the Islamic State-affiliated jihadis fighting to establish a caliphate there are largely teenaged, with some as young as thirteen participating in the killing.

“They are just barely out of teenage life. And they take command from boys in their early to mid-20s,” a woman identified as Norma told the Philippine Inquirer, following her escape from the city. “That is why I addressed most of them as orak (boy) when I conversed with them while me and my family walked out of Marawi the day after the siege started.”

Norma described the boys as “playing,” apparently enjoying the fear of civilians at the sound of gunfire and taking the time to enjoy the loot they robbed from local groceries.

“The boldness and daring that are inherent in the youth are being exploited to advance aims that these boys do not understand,” another woman, Faridah, told the newspaper, asking, “I really wonder if they ever realize the implications of what they are doing.”

The Inquirer says the witnesses estimated children as young as 13 were participating in the violence.

The Islamic State terrorists overrunning Marawi, a city of some 200,000 on Mindanao, are members of a terrorist organization known as the Maute group. The jihadists attacked Philippine police last week during a siege of the suspected hideout of Isnilon Hapilon, the head of Abu Sayyaf, another jihadist group that has pledged allegiance to the Islamic State. The jihadists interrupted the police operation and then began attacking authorities and positioning themselves to turn Marawi into an Islamic city, raising the ISIS flags over mosques and killing anyone identified as Christian.

Survivors have reported that the terrorists are stopping civilians attempting to flee and forcing them to recite Islamic prayers. Those who cannot recite them are killed immediately, even those who identify as Muslim. Police found a pile of bodies this week labeled “hypocrites,” which they believe to be Muslims that the jihadists found insufficiently devout. Islamic State supporters around the world have used this tactic when attempting to establish an Islamic stronghold.

President Rodrigo Duterte implemented a 60-day martial law status over Mindanao last week in response to the raid, telling soldiers to “spare no one” and giving them the ability to arrest individuals and search homes without warrants. During his announcement of the martial law rule, he warned soldiers not to violate human rights norms, though he later joked that he would protect them if they raped up to three women while on the job.

While both Maute and Abu Sayyaf are indigenous terrorist groups, Philippine police have identified Malaysian and Indonesian terrorists among the criminals, with one official describing the battle for Marawi as an “invasion.”

Philippine police say the objective of the Maute terrorists in Marawi appears to be to legitimize themselves as heads of a true Islamic State “wilayat,” or province. “They wanted to show the world that there is an ISIS branch here which can inflict the kind of violence that has been seen in Syria and Iraq,” military chief of staff Gen. Eduardo Año told reporters. Islamic State caliph Abu Bakr al-Baghdadi has not issued a personal statement accepting Maute and Abu Sayyaf as Islamic State members, though reports place him in Mosul, Iraq – ground zero of the global coalition’s war on the terrorist group.

Año told reporters that, while violence in Marawi continues to rage, authorities believe that 70 percent of the city is free of jihadist control. Authorities place the death count so far at over one hundred, including 65 jihadists and 15 Philippine soldiers. At least two mass graves of civilians have surfaced.