The inhabitants of the majority Shiite village of Al-Rashad in the eastern Diyala province killed 11 people on Wednesday in the predominantly Sunni neighbouring hamlet of Nahr al-Imam, the security official who preferred to remain anonymous said.

The assailants accused the residents of Nahr al-Imam of being behind an attack on Al-Rashad the day before in which 15 people were killed, an increase from an initially reported toll of 11.

Another 26 people were injured in the Tuesday attack on Al-Rashad, according to the latest figures from security sources.

The Sunni militant IS group -- which considers Shiites to be "heretics" -- claimed the Al-Rashad attack on Wednesday night.

Al-Rashad is known to have many members of security forces among its residents and is populated mostly by members of the Bani Tamim tribe, from which the governor of Diyala hails.

The Iraqi Fiqh Council, the authority on Islamic jurisprudence for Sunnis in the country, condemned the "terrorist attack" on Al-Rashad, as well as the "horrific revenge" on Nahr al-Imam.

The IS group took over large swathes of Iraq and Syria in 2014, declaring itself a new "caliphate" for Muslims.

Iraq declared the defeat of IS in December 2017, but a low-level insurgency has persisted in the country, flaring up at various points.

A UN report early this year estimated that around 10,000 IS fighters remained active across Iraq and Syria.