Baghdad: The Sunni tribes from Iraq who chose to fight against the barbaric extremist group Islamic State were on the receiving end of a bloody revenge meted out by the ISIS as over 200 bodies were found in the mass graves found recently in Anbar province, reports said Sunday.

Albu Nimr tribe, which was said to have taken the side of the US and Iraqi government against the ISIS, fought valiantly for weeks before they ran out of ammunition and food supply.

After 150 members of the tribe were massacred by the ISIS and their bodies were found in a mass grave in Ramadi on Thursday, about 50 more members of the group were kidnapped in Hit in Anbar province on early Saturday, the CNN reported.

Those abduct are feared to be dead, like over a hundred others who were killed last week, a tribal leader, Sheikh Nabil Al-Ga'oud told the CNN.

Albu Nimr tribe has tens of thousands of members and are ready to fight the ISIS to take back the province of Anbar from the ISIS, the report added.

According to a Daily Mail report, the ISIS also massacred 30 tribesmen in broad daylight in the centre of Hit. They were paraded through the streets and declared to be apostates on loudspeakers and then shot one by one after being lined up.

The ISIS' barbaric onslaught continues across Iraq and Syria despite US coalition carrying air strikes to check their advance.

The ISIS overran a huge chunk of territory across Iraq and Syria in June this year and established an Islamic Caliphate, unleashing a terror sparked by massacre of thousands and rape and torture of women.