Under the cover of last year’s war, the militant group Hamas carried out the extrajudicial murders of at least 23 members of the rival Palestinian Authority in Gaza, and acted in concert with Israel to torture dozens of others, including political rivals of the Hamas leadership.

“In the chaos of the conflict, the de facto Hamas administration granted its security forces free rein to carry out horrific abuses, including against people in its custody,” said Philip Luther of Amnesty International, which released a report on the killings on Wednesday.  “These spine-chilling actions, some of which amount to war crimes, were designed to exact revenge and spread fear across the Gaza Strip.”

While Israel’s aerial bombardment wreaked havoc in Gaza last July and August, Hamas executed the victims – war crimes, according to the rights group.  Some were on trial at the time, having been charged with collaboration, or were awaiting the outcome of appeals against death sentences from a military court in Gaza on the same charges.  Two had been convicted and were serving prison terms when they were killed.

On one date, Hamas executed six men before a crowd of hundreds that included children.  Amnesty says Hamas had declared them collaborators who had been sentenced to death in “revolutionary courts” before they were dragged on the ground to be shot individually, and then sprayed with bullets.