Children were slaughtered, tortured, sexually attacked and used as human shields by pro-government Syrian forces, according to a damning United Nations report released late on Monday. 

"Children were victims of killing and maiming, arbitrary arrest, detention, torture and ill-treatment, including sexual violence, by the Syrian Armed Forces, the intelligence forces, and the Shabbiha militia," the U.N.'s Special Representative for Children and Armed Conflict Radhika Coomaraswamy said in a release issued along with the report. 

Shaam News Network / AFP - Getty Images

Residents of Houla ride in the back of a pick-up truck on June 5, according to Syrian opposition's Shaam News Network. In May, a massacre in Houla claimed 108 lives including those of 49 children, according to UN figures.

The shabiha are a pro-government militia that recruits largely from the Alawite community- the same Muslim sect as President Bashar Assad. Sunnis, who make up the majority of the rebels, are an estimated 74 percent of the population.

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In an interview with the BBC, Coomaraswamy said she had learned of "horrific" reports in Syria. She told the BBC:

"We are really quite shocked. Killing and maiming of children in cross-fire is something we come across in many conflicts but this torture of children in detention, children as young as 10, is something quite extraordinary, which we don't really see in other places."

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"We also had testimonies and saw children who had been tortured, and who carried the torture marks with them. We also heard of children being used -- this was recounted to us by some children -- of being put on tanks and being used as human shields so that the tanks would not be fired upon."

Coomaraswamy also criticized the rebellion's main armed group for its treatment of children.

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"For the first time we heard of children being recruited by the Free Syrian Army mainly in medical and service orientated jobs but still on the front line," she told the BBC.

The U.N. says Syrian forces have killed more than 10,000 people in the crackdown on an uprising inspired by revolts which toppled four Arab leaders in 2011. Syrian authorities say foreign-backed militants have killed 2,600 soldiers and police. 

Activists say Syria's army and pro-Assad militia have committed two massacres in the last two weeks, in the Houla region and a farming hamlet called Mazraat al-Qubeir. Syrian authorities blamed the killings on "terrorists."

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The United States and other Western nations who have been critical of Assad's regime had little new to suggest to end Syria's 15-month long crisis, which has seen the United Nations Security Council deadlocked amid continued support for Assad by veto-holding Russia and China.

The use of civilians as human shields has been reported before.  On March 25, Human Rights Watch released a video purportedly showing how Syrians were forced to walk in front of armored personnel carriers: 

The international rights organization also quoted a resident of Kafr Nabl as saying:

"They took maybe 25 people, including me. There were also eight children, aged from 10 to 15, among us. They made us march in front and around the military vehicles to some houses where they were searching for wanted opposition activists. We marched for about 600 meters. They were insulting us the whole time. They arrested several people from the houses. Then they made us march back to their base, after which they released all of us, apart from the detained activists. The whole operation lasted for about two hours."

Reuters and The Associated Press contributed to this report.

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