Islamic State extremists lined up and shot dead at least 50 tribesmen and women in Iraq’s Anbar province, officials said Saturday, the latest mass killing attributed to the group.

The shooting happened late Friday in the village of Ras al-Maa, north of the provincial capital of Ramadi, Anbar councilman Faleh al-Issawi said.

Militants accused the men and women of Al Bu Nimr tribe of retaliating against them after being displaced from their homes when the group seized the Anbar town of Hit last month, Issawi 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,” he said.

An official in the Anbar governor’s office confirmed the death toll. He spoke on the condition of anonymity because he is not authorized to brief journalists.

On Thursday, authorities found the bodies of 48 Sunni tribesmen in Anbar who are believed to have been killed by the Islamic State.

The militant Islamist group has overrun a large part of Anbar province in its push to expand its territory, which 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, have repeatedly described the Iraqi tribes as key elements in the fight against the group, since they are able to penetrate areas inaccessible to airstrikes and ground forces.

Meanwhile Saturday, the U.N. mission in Baghdad said that at least 1,273 Iraqis were killed in violence in October, a slight increase from September. The worst-hit city was Baghdad, with 379 civilians killed, the report said.

The U.N. figures do not take into account casualties in Anbar province or other militant-held parts of Iraq.

On Saturday afternoon, a car bomb exploded near an outdoor market in the town of Youssifiyah, just south of Baghdad, killing 12 people and wounding 25, police said.

In eastern Baghdad, three people were killed by a bomb blast near a tent for Shiite pilgrims heading to the holy city of Karbala to observe the religious holiday of Ashura.

Later, police said a suicide car bomber struck a police checkpoint in Baghdad’s southern district of Dora, killing six policemen and six civilians.

— Associated Press