Courts have handed down hundreds of death and life sentences in recent years to Iraqis convicted of "terrorism", in trials that rights groups have denounced as hasty.

Under Iraqi law, terrorism and murder offences are punishable by death, and execution decrees must be signed by the president.

A security source said eight Iraqis "convicted of terrorism and of being members of the Islamic State group were executed by hanging" Thursday at Al-Hut prison in the city of Nasiriyah "under the supervision of a justice ministry team".

They were hanged "under Article 4 of the anti-terrorism law", the source told AFP on condition of anonymity due to the sensitivity of the issue.

A medical source said the health department had received the bodies of eight executed people.

Al-Hut is a notorious prison in Nasiriyah whose Arabic name means "the whale", because Iraqis believe that those jailed there never walk out alive.

"That these executions continue to take place is a clear signal from Iraqi authorities that all calls for halting them are falling on deaf ears," said Amnesty International's Iraq researcher Razaw Salihy.

She said executions were happening "despite evidence of years of unfair trials and human rights violations" that landed men on death row.

On May 6, Iraq hanged 11 people convicted of "terrorism", security and health sources told AFP. It was the second such group put to death since April 22.

- 'Deep concern' -

Iraq has been criticised for the trials, with the "terrorism" offence carrying the death penalty regardless of whether the defendant had been an active fighter.

Rights groups denounced the proceedings as rushed, warning that confessions were sometimes believed to have been obtained under torture.

Every time, executions "send shudders throughout the country for families whose loved ones have been languishing in death row cells wasting away from the inhumane conditions," Amnesty's Salihy said.

While authorities "continue to fail to notify lawyers and families prior to executions," she said, "families now fear turning up for visits only to be told your relative was already executed."

In late January, UN experts looking into capital punishment in Iraq expressed their "deep concern at reports that Iraq has begun mass executions in its prison system".

The independent experts, who are appointed by the UN Human Rights Council but do not speak on its behalf, mentioned in their statement executions carried out late last year in the Nasiriyah prison.

The statement said that "13 male Iraqi prisoners -- previously sentenced to death -- were executed on 25 December 2023", calling it "the largest number of convicted prisoners reportedly executed by the Iraqi authorities in one day" since November 16, 2020, when 20 were executed.

The IS group overran large swathes of Iraq and neighbouring Syria in 2014, proclaiming its "caliphate" and launching a reign of terror.

It was defeated in Iraq in 2017 by Iraqi forces backed by a US-led military coalition, and in 2019 lost the last territory it held in Syria to US-backed Kurdish forces.

But its remnants continue to carry out deadly hit-and-run attacks and ambushes, particularly from remote areas and desert hideouts.