An international childrens' rights organisation has released a report highlighting the severe plight of Syrian children during the country's two-year conflict.
UK-based Save the Children said on Wednesday that at least two million children in the country face malnutrition, disease, early marriage and severe trauma.
It said a substantial number of youth have been shot at, raped and tortured.
"This a war where woman and children are the biggest casualty," Save the Children's chief Justin Forsyth told the Reuters news agency in Lebanon, where 340,000 Syrians have fled to.
The Save the Children report cited new research carried out among refugee children by Bahcesehir University in Turkey which found that one in three reported having been punched, kicked or shot at.
Refugees say that soldiers loyal to President Bashar al-Assad's regime are directly targeting children.
Forsyth said he met one child who said he was in a prison cell with 150 people, including 50 children.
"He was taken out every day and put in a giant wheel and burnt with cigarettes. He was 15. The trauma that gives a child is devastating."
The report also said two-thirds of children surveyed said that they had been separated from members of their families due to the conflict and a third said they had experienced the death of a close friend or family member.
"All these children tell you these stories in a matter of fact way and then you realise that there are layers and layers of emotional trauma there," said Forsyth.
Forsythe said he met a Syrian refugee boy, 12, who saw his best friend killed outside a bakery.
In-depth coverage of escalating violence across Syria
Forsyth also said that rape is being used to deliberately punish opponents of the government, adding that it is under-reported due to the sensitivity of the issue, especially among conservative communities.
"In most conflicts, over 50 percent of rapes are against children. And I am sure that is the case in this conflict too."
Nicole Itano, a spokesperson for Save the Children, said conditions in refugee camps housing displaced Syrians were dire.
"Schools are closed down; food is running out [and] water is making people very, very sick because it's dirty, because the sanitation system has broken down," she told Al Jazeera.
"So these children, these families come across the border - it's an incredibly dangerous journey - and then they reach here and they're exhausted, scared and hungry and they're ending up in camps."
Fear of sexual violence was repeatedly cited to Save the Children as one of the main reasons for families fleeing their
homes, according to the report.
Syria's conflict started with peaceful protests against Assad's rule. His forces killed many protesters and arrested thousands before the revolt turned into a civil war.