Militants of the Islamic State group tortured and abused Kurdish children, aged 14 to 16, abducted from the Syrian border town of Kobani, Human Rights Watch, or HRW, said, in a statement released Tuesday. The findings of the rights group are based on interviews conducted with several children who were among the over 150 boys abducted from Kobani by ISIS in May.

Four of the children who were released by the Islamic State group last month told HRW that the militants “beat the children who tried to escape, did poorly in compulsory religious lessons, or did anything else perceived by their captors as misbehaving.”

The children added that those whose families were a part of the Kurdish YPG forces battling ISIS in Kobani were made to suffer the most. “They (ISIS) told them (the children) to give them the addresses of their families, cousins, uncles, saying ‘When we go to Kobani we will get them and cut them up,’” a 15-year-old Kurdish boy told HRW.

The children also reportedly described being forced to pray five times a day and undergo intense religious indoctrination. ISIS "teachers" also forced them to watch videos of the group's militants beheading captives.

“Those who didn’t conform to the program were beaten. They beat us with a green hose or a thick cable with wire running through it…They made us learn verses of the Quran and beat those who didn’t manage to learn them,” one of the Kurdish boys, 16, told HRW. “They sometimes found excuses to beat us for no reason.”

ISIS has taken hundreds of Kurds, including many children, captive over the course of the year, as it expands into predominantly Kurdish areas in northern Syria. On Monday, the Syrian Observatory for Human Rights said that ISIS had released 93 Kurdish hostages abducted in February. However, an undisclosed number of Kurds are still believed to be held by the Islamic State group, according to media reports

“Since the beginning of the Syrian uprising, children have suffered the horrors of detention and torture, first by the Assad government and now by ISIS,” Fred Abrahams, special advisor for children’s rights at HRW, said, in the statement. “This evidence of torture and abuse of children by ISIS underlines why no one should support their criminal enterprise.”