"Women and children have been buried alive in mass graves by the fanatics terrorising Iraq, it was claimed last night.
Up to 500 members of the ancient Yazidi sect have suffered the appalling fate, according to an Iraqi minister.
Fighters from the Islamic State group are also accused of kidnapping 300 women to use for sex or as domestic slaves.
Some 150,000 Yazidis fled their homes after the militants overran their main town of Sinjar in northern Iraq last week...
Mohammed Shia al-Sudani, who is Iraq's human rights minister, said that he had seen pictures of militants cheering and waving their weapons over lines of dead Yazidis.
'We have striking evidence obtained from Yazidis fleeing Sinjar and some who escaped death, and also crime scene images that show indisputably that the gangs of the Islamic State have executed at least 500 Yazidis after seizing Sinjar,' Mr al-Sudani told reporters.
'Some of the victims, including women and children, were buried alive in scattered mass graves in and around Sinjar.'
Tens of thousands of Yazidi refugees who fled the militants' advance found themselves trapped on barren Mount Sinjar last week.
Scores of children, women and elderly people died of dehydration and starvation as their food and water supplies ran out in scorching temperatures."