Casualties reported following shooting at military parade in southwest Iran

At least 10 were killed when gunmen opened fire on people from behind a viewing stand at Qods Boulevard of Ahvaz during the morning parade held to mark the former Iraqi dictator Saddam Hussein's invasion of Iran in the 1980s.

Iran was holding similar parades in several cities including the capital Tehran and the port of Bandar Abbas on the Gulf.

This is a developing story and will be updated accordingly.

The IRNA report said those wounded in the attack Saturday included a woman and a child. Paramedics could be seen helping someone in military fatigues lying on the ground. There has been no claim of responsibility for the attack in the city of Ahvaz.

Tensions between Iran and Saudi Arabia have surged in recent years, with the two countries supporting opposite sides in wars in Syria and Yemen and rival political parties in Iraq and Lebanon.

Videos of the attack published online and by local media outlets show scenes of chaos as soldiers and civilians flee gunfire and attempt to treat the wounded. The semi-official Tasnim news agency said at least eight member of the Guard had been killed.

Who carried out the assault also remained in question.

Among those involved are members of the Revolutionary Guard, a paramilitary force answerable only to Supreme Leader Ayatollah Ali Khamenei. The province in the past has seen Arab separatists attack oil pipelines.

Iran is also now facing intensified attacks in its Kurdish-majority provinces (Rojhilat) and along its Western border with the Kurdistan Region, where Kurdish opposition groups operate.

The assault shocked Tehran, which largely has avoided militant attacks in the decades after the tumult surrounding the Islamic Revolution.