LONDON: Men and boys from Iraqi villages recaptured from ISIS in the operation to retake Mosul have been unlawfully detained, tortured and ill-treated by tribal militia, Amnesty International said Thursday.

The Hashed al-Ashaeri (Tribal Mobilization), made up of Sunni tribal militiamen, have been carrying out revenge attacks in villages south-east of Mosul against those residents suspected of having ties to ISIS, the London-based rights group said.

Some were beaten with metal rods and given electric shocks, and some were tied to the bonnets of vehicles and paraded through the streets or placed in cages, it said, citing interviews with local officials and village witnesses.

"There is strong evidence that Sabawi tribal militia members have committed crimes under international law by torturing and otherwise ill-treating residents in Qata al-Sabaween (Sabaween sector) in revenge for crimes committed by ISIS," said Lynn Maalouf, Amnesty's deputy director for research in Beirut.

"There is no doubt that ISIS fighters who are suspected of committing crimes must be held accountable in fair trials.

"But rounding up villagers and forcing them to endure public humiliation or other violations, including torture, is no way of securing justice, truth and reparation for victims of ISIS crimes."

Amnesty warned in a report on Oct. 18 about the possibility of revenge attacks directed at Sunnis suspected of being complicit with ISIS, urging Iraqi authorities to act to prevent a repeat of past abuses.