At least 24 people were killed and 53 were injured after suspected militants attacked a military parade in southwest Iran on Saturday morning, state news agency IRNA reported. At least eight of those killed were members of the elite Revolutionary Guard Corps.

The shooting, in Ahvaz city, lasted around 10 minutes. Security forces are reportedly now in control of the situation.

The parade was being held to mark the anniversary of the start of the war with Iraq in 1980. Four unidentified assailants fired bullets at the civilian crowd watching the ceremony at around 9 am local time (11 am Indian time), Fars news agency reported.

Ali Hosein Hoseinzadeh, deputy governor in Khuzestan province, said two attackers were killed and two were arrested, reported Al Jazeera.

The Islamic State claimed responsibility for the attack, AFP quoted its propaganda agency Amaq as saying.

But the state media reported that a separatist group called Al-Ahwaz, affiliated to the Saudi Arabia regime, has accepted responsibility in a message on social media. This came hours after Iran’s Foreign Minister Javad Zarif blamed a “foreign regime” for the attack.

“The group has carried out a few sabotage operations in Khuzestan province during the past years,” said an unidentified senior provincial police officer.