Young boys abducted by Islamic State are being sent to jihad training camps where they are forced to practise beheading infidels by using dolls.

The Yazidi boys are told the exercise is part of their "re-education" as Islamic State attempts to train up a new generation of terrorists and suicide bombers.

Details of the jihad camps for children emerged for the first time when Associated Press interviewed a Yazidi teen who had managed to flee one of the camps.

He described how boys were forced to convert to Islam and brainwashed into becoming jihadi fighters after Islamic State captured Yazidi towns in Iraq last year. The older men were murdered and the girls and women taken and married, used or sold as sex slaves. The boys were taken for "ashbal", Arabic for "lion cubs", to be trained into child jihadists.

Hundreds of boys have been captured and indoctrinated by being shown beheading videos then given a sword and a doll and told to practise. Islamic State claims to have dozens of similar camps.

"Then they taught me how to hold the sword, and they told me how to hit. They told me it was the head of the infidels," said one boy, Yahya, aged 14, who described how he kept getting it wrong and had to try two or three times to chop the doll's head off. He had been captured with his little brother and his mother and taken to the Farouq jihadi training camp after Islamic State seized their home town of Sulagh in August.

The boys trained up to 10 hours a day, studying the Qu'ran and learning to use weapons. They were told that if they did not perform the tasks they were given, they would be killed.

Of the beheading video, Yahya said: "I was scared when I saw that. I knew I wouldn't be able to behead someone like that. Even as an adult."

A video last week showed a boy beheading a Syrian soldier. Another video last month showed 25 children shooting Syrian prisoners in the head.

Sunni Muslim boys are also targeted for the training camps by Islamic State recruiters who distribute sweets along with propaganda at street corners.

According to the Syrian Observatory for Human Rights, at least 1,100 Syrian children under 16 joined Islamic State this year and 52 have died while fighting, including eight suicide bombers.