Islamic State militants have justified their actions in seizing thousands of women from the Iraqi Yazidi minority to be sold as sex slaves.

In their new English-language online propaganda magazine Dabiq, the group reveals that the act is according to theological rulings of early Islam.

The article said that the Yazidis, a Kurdish minority living in Iraq, may legitimately be captured and forcibly made concubines.

"One should remember that enslaving the families of the kuffar - the infidels - and taking their women as concubines is a firmly established aspect of the Shariah, or Islamic law," the group said in the magazine published Sunday, CNN reported.

CNN noted that hundreds of Yazidi women and girls were sold or given away to militants as "spoils of war."

Most Muslims throughout the world have denounced the IS as having nothing to do at with Islam despite the groups claim to wage war for it.

Britain's Telegraph newspaper said that the magazine is mostly devoted to theological justifications for Islamic State behavior.

An article titled "The Revival of Slavery before the Hour," referring to Judgment Day revealed that the enslaved Yazidi families are now sold as the mushrikin were sold by the Companions before them

The article says that the large-scale enslavement of mushrik families is probably the first since Shariah law was abandoned. It mentioned a similar but smaller scale of enslavement of Christian women and children in the Philippines and Nigeria.

A September report by Al Arabiya said as many as 3,000 Iraqi women have been forced into sex slavery at brothels run by British female jihadists.

Meanwhile, two U.N. officials issued a joint statement in August on the "barbaric acts" of sexual violence committed by the jihadists.

"We condemn, in the strongest terms, the explicit targeting of women and children and the barbaric acts the 'Islamic State of Iraq and the Levant' has perpetrated on minorities in areas under its control," said Nickolay Mladenov and Zainab Hawa Bangura.

They stressed that acts of sexual violence are "are grave human rights violations that can