The five were killed "during a reconnaissance and surprise operation by forces of the resistance this morning in Iraq's Diyalah province," northeast of Baghdad, the statement said.

The "resistance" is a term used for militias operating in Iraq and Syria with Tehran's support, and trained by the Revolutionary Guards.

Abu Zahi was "the mastermind of the recent terrorist crime in Ahvaz," the statement added.

The attack on a military parade in the mainly ethnic Arab city of Ahvaz in southwestern Iran left 24 people dead last month.

Claims of responsibility for that attack were posted by both the jihadists of the Islamic State group and by a separatist group calling itself Ahvaz National Resistance.

On October 1, Iran said it had struck jihadists in Syria with ballistic missiles and combat drones in retaliation for the September attack.