Dozens of children captured by ISIS have been forced to "practice" beheadings on dolls, a boy who fled a training camp run by the Islamist terror group revealed.

"They taught me how to hold the sword, and they told me how to hit," the boy, renamed Yahya by his captors, recounted to the Associated Press. "They told me it was the head of the infidels," he said.

The 14-year-old's family belongs to the Yazidi religious minority, whose towns and villages had been overrun by ISIS last year. The terror group, which controls large swaths of territory across Iraq and Syria, killed older men and turned women and girls into sex slaves for its fighters. But it apparently sought to indoctrinate and re-educate Yazidi boys, seeking to convert them into jihadi extremist fighters.

ISIS is actively recruiting teens and children, using cash, gifts, intimidation and brainwashing, the newspaper noted. The organization, known for its brutal treatment of local residents and foreign captives, has turned many kids into killers, and a boy who appeared younger than 13 was seen decapitating a Syrian army captain in a recently released propaganda video.

Yahya and his family were taken when ISIS seized the Iraqi town of Sulagh in August. The boy was given a Muslim Arabic moniker to replace his Kurdish name and was forced to attend a training camp for boys aged 8 to 15, where he spent nearly five months, the AP detailed.

He was told that Yazidis are "dirty" and should be killed, and his training, which lasted 8-to-10 hours per day, included exercises, weapons drills and Quranic studies. Instructors sometimes forced children to hit each other, and at one point Yahya punched his 10-year-old brother, knocking out a tooth.

The trainer "said if I didn't do it, he'd shoot me," Yahya explained. "They ... told us it would make us tougher. They beat us everywhere."

Abu Hafs Naqshabandi, a Syrian sheikh in the Turkish city of Sanliurfa, said that ISIS aims to "(plant) extremism and terrorism in young people's minds," adding that he was "terribly worried about future generations."

Meanwhile, residents of ISIS-controlled areas are finding it difficult to gain access to unfiltered information as the terror organization has severely restricted the use of the Internet, Vice noted.

In its de facto capital of Raqqa, even higher-ranking militants are allowed to surf the web only under supervision and at monitored internet cafes, human-rights groups reported. ISIS may be attempting to hinder the work of citizen journalists and human rights groups, which have been sending information out of ISIS territory.

Controling the Internet follows a similar path to sending children to "training" camps, because they both prevent outside information from threatening the status quo and the authority of ISIS.