Islamist militants shot dead at least 29 people including women and children in an attack Saturday on an Iranian military parade claimed by the Islamic State group.
State television gave a casualty toll of 29 dead and 57 wounded, while official news agency IRNA said those killed included women and children among spectators at the rally.
The attack in the southwestern city of Ahvaz came as the country marked the anniversary of the start of its 1980-1988 war with Saddam Hussein’s Iraq and prompted President Hassan Rouhani to warn of a “crushing response”.
“The response of the Islamic Republic of Iran to the smallest threat will be crushing”, Rouhani said on his official website.
“Those who give intelligence and propaganda support to these terrorists must answer for it.”
Foreign Minister Mohammad Javad Zarif said in a tweet that the attack near the Iraqi border was carried out by “terrorists recruited, trained, armed & paid by a foreign regime”.
“Iran holds regional terror sponsors and their US masters accountable for such attacks,” he wrote.
IS jihadists said via their propaganda mouthpiece Amaq that “Islamic State fighters attacked a gathering of Iranian forces” in Ahvaz.
Armed forces spokesman Brigadier General Abolfazl Shekarchi said the dead included a young girl and a former serviceman in a wheelchair.
“Of the four terrorists, three were sent to hell at the scene, while the fourth who had been wounded and arrested went to hell moments ago due to his severe wounds,” Shekarchi told state television.
Khuzestan deputy governor Ali-Hossein Hosseinzadeh told the semi-official ISNA news agency that “eight to nine” troops were among those killed, as well as a journalist.
In a message of condolence to Russia’s close regional ally, President Vladimir Putin said he was “appalled by this bloody crime”.
“This event once again reminds us about the necessity of an uncompromising battle against terrorism in all of its manifestations.”
The devastating attack comes as the United States re-imposed crippling sanctions on the country last month, with a new round of even harsher sanctions targeting the vital oil sector coming into effect on November 5.