nhk world's hideki nakayama has gone to southern iraq to take a close look. >> reporter: this is howhey are being taught to hold a gun. they are learning self-defense skills to protect themselves during a battle. these fighters of the popular mobilization forces are being trained in southern iraq. the group was formed in june last year to counter the islamic state militants after it had rapidly gained ground. iraq's most influential shia clerk, ayatollah sistani, called for the group to be formed. he has repeatedly warned the sunni-dominated islamic state group is dangerous. the popular mobilization forces are set to have more than 100,000 fighters. sistani ordered junior and senior high school students were ordered to take part in training during their summer break. it's believed that some children participated in the fight. training instructors are former members of the iraqi military. some also fought against islamic state militants. 27-year-old haidar al budairy is one of them. he has fought with the militants 16 times. he shares his experience with the trainees every time he ret