ISIS fighters reportedly surrender after using 700 boys as human shields during a battle at a prison in Syria

• ISIS fighters stormed a prison and used 700 boys as human shields, according to multiple reports.
• Many of the boys were brought over to Syria by their parents, including 150 non-Arab foreigners.

Islamic State fighters who attacked a prison in Syria and used 700 boys detained in the facility as human shields have surrendered, a US-backed militia announced on Wednesday.

"The Peoples' Hammer Operation has culminated with our entire control of the al-Sina'a prison in al-Hasaka and the surrendering of all [Islamic State] terrorists," a spokesperson for the Syrian Democratic Forces militia wrote on Twitter.

A video posted by the spokesperson to Twitter appeared to show Islamic State fighters lined up outside the prison after surrendering to the Kurdish-led militia.

On Thursday, Islamic State fighters attacked and took control of part of the prison in northeast Syria — using hundreds of boys detained at the facility as human shields, the New York Times reported.

What followed was nearly a week of fighting between the Islamic State and the SDF.

American ground troops engaged with ISIS on Monday after the US launched airstrikes to aid the SDF in fighting to recover the complex, the Times reported.

The SDF said on the same day that they retook of one of the prison's three buildings and that 300 Islamic State fighters had surrendered, the Times said.

But they also said that the remaining ISIS forces took around 700 boys and teenagers hostage after moving into their dormitory, the Guardian reported.

Leaders of the militia reported multiple deaths and injuries among the children as the boys were caught in the crossfire, according to the Guardian.

Many of the children were brought to Syria when their parents moved there to join ISIS and have yet to be repatriated to their home countries. According to the Times, some of those detained are as young as 12, and the group includes 150 non-Arab foreigners.

SDF leadership said it held the ISIS fighters inside the prison responsible for the safety of the children, the Times reported.

In a press release on Monday, UK-based nonprofit Save the Children said it had received audio recordings from the boys, including one boy pleading for help.

"Save the Children cannot independently confirm these claims, but ISIS-affiliated fighters have used children as human shields in previous years," the statement read.

"All those involved in the fighting at Guweiran prison have a responsibility to protect these children from harm," Sonia Khush, Save the Children's Syria Response Director, said in a statement released by the nonprofit. "And we urge them to take all possible steps immediately to ensure that these children can leave in safety."

Meanwhile, the Telegraph reported that it obtained voice notes from an Australian teen begging for help. The teen told the outlet that he'd been wounded in a helicopter strike.

"I've seen a lot of bodies of kids, eight years, 10 years, 12 years. My friends got killed here. I'm by myself, I'm very scared, there's a lot of people dead, a lot of people injured," he said, according to the Telegraph.

Human Rights Watch also said it had heard a recording of a teen saying he had seen bodies lying around the prison, the Times reported.

Save the Children's Khush pinned partial responsibility for the boys' safety on foreign governments, accusing them of thinking they could "simply abandon their child nationals in Syria."

"Risk of death or injury is directly linked to these governments' refusal to take them home," she said.

"All foreign children must be repatriated — with their families — without any further delay. The international community cannot have the blood of any of these children on their hands," added Khush.