Graphic Photos: In latest mass killing, ISIS militants line up & execute 50 tribesmen & women in Iraq

Islamic State group militants have lined up and executed at least another 85 tribesmen in Iraq's Anbar province after accusing the tribe of retaliating against them.

Mass killings have become a near daily occurrence across the swathes of Syria and Iraq controlled by ISIS as it seeks to impose a brutal form of sharia law across the region.

The shooting, confirmed by Iraqi officials, occurred late Friday in the village of Ras al-Maa, north of the provincial captial Ramadi.

ISIS had accused the Al Bu Nimr tribe of retaliating against them after being displaced from their homes when the militants seized the town of Hit last month.

It comes just days after the bodies of another 220 Al Bu Nimr tribesmen were found in two separate graves, bringing the total number of people from the tribe executed around 300.

Faleh al-Issawi, a councillor of the Anbar region, said: 'These killings are taking place almost on a daily basis now in the areas under the control of the Islamic State group and they will continue unless this terrorist group is stopped.'

The Islamic State group has overrun a large part of Anbar province in its push to expand its territory, which currently stands at about one-third of both Iraq and Syria.

Officials with the Iraqi government, as well as officials with the U.S.-led coalition targeting the extremists, repeatedly have said that Iraqi tribes are key in the fight against the Islamic State group since they are able to penetrate areas inaccessible to airstrikes and ground forces.

More than 150 members of the Sunni Albu Nimr tribe were found in a mass grave near Ramadi in Anbar province on Thursday, while the corpses of another 48 members were discovered near Hit.

In a further frightening development ISIS militants massacred 30 men in broad daylight in the centre of Hit, which is also in Anbar, parading them through the streets and using loudspeakers to declare them apostates.

The murdered men were thought to be local tribesmen who had allied with the Iraqi government and were helping to organise anti-ISIS operations throughout the province.

Meanwhile, the United Nations mission in Baghdad said that at least 1,273 Iraqis were killed in violence in October a slight increase compared to last month amid the Islamic State group's assault.

However, the figures do not take into account casualties in Anbar province or some other militant-held parts of Iraq.

The UN report said violence killed 856 civilians and 417 members of Iraq's security forces, while attacks wounded 2,010 Iraqis. The worst-hit city was Baghdad, with 379 civilians killed.

The UN has said September's death toll was 1,119 Iraqis killed.