DUBAI--Iran's elite Revolutionary Guards vowed on Sunday to exact "deadly and unforgettable" vengeance for an attack on a military parade that killed 25 people, including 12 of their comrades, and Tehran accused Gulf Arab states of backing the gunmen.
Saturday's assault, one of the worst ever against the most powerful force of the Islamic Republic, struck a blow at its security establishment at a time when the United States and its Gulf allies are working to isolate Tehran.
"Considering (the Guards') full knowledge about the centres of deployment of the criminal terrorists' leaders ..., they will face a deadly and unforgettable vengeance in the near future," the Guards said in a statement carried by state media.
Four assailants fired on a viewing stand in the southwestern city of Ahvaz where Iranian officials had gathered to watch an annual event marking the start of the Islamic Republic's 1980-88 war with Iraq. Soldiers crawled about as gunfire crackled. Women and children fled for their lives.
The assailants had hidden weapons near the parade route several days in advance, said Brigadier General Abolfazl Shekarchi, a senior spokesman for Iran's armed forces. "All four terrorists were quickly neutralised by security forces," Shekarchi told state television. "A four-year-old girl and a wheelchair-bound war veteran were among the dead."
Islamic State's Amaq agency posted a video of three men in a vehicle who it said were on their way to carry out the attack.
A man wearing a baseball cap emblazoned with what appears to be a Revolutionary Guard logo discussed the impending attack in Farsi in the video. "We are Muslims, they are kafirs (non-believers)," the man says. He adds: "We will destroy them with a strong and guerrilla-style attack, inshallah (God willing)."
Ahvaz National Resistance, an Iranian ethnic Arab opposition movement which seeks a separate state in oil-rich Khuzestan province, also claimed responsibility for the attack. Neither of them provided evidence.
There has been a blizzard of furious statements from top Iranian officials, including President Hassan Rouhani, accusing Iran's adversaries the United States and Gulf states of provoking the bloodshed and threatening a tough response.
Nikki Haley, U.S. ambassador to the United Nations, rejected Rouhani's accusations. "He's got the Iranian people ... protesting, every ounce of money that goes into Iran goes into his military, he has oppressed his people for a long time and he needs to look at his own base to figure out where that's coming from," she told CNN.
Senior commanders of the Islamic Revolutionary Guards Corps (IRGC) have said the Ahvaz attack was carried out by militants trained by Gulf states and Israel, and backed by America. But it is unlikely the IRGC will strike any of these foes directly.
The Guards could put on a show of strength by firing missiles at opposition groups operating in Iraq or Syria that may be linked to the militants who staged the attack. They are also likely to enforce a tight security policy in Khuzestan province, arresting any perceived domestic opponents including civil rights activists.
Three Arab activists told Reuters that security forces, especially the intelligence branch of the Revolutionary Guards, had detained more activists in Ahvaz.
Rouhani engineered Iran's 2015 nuclear deal with world powers that ushered in a cautious detente with Washington before tensions flared anew with President Donald Trump's decision in May to pull out of the accord and reimpose sanctions on Tehran. The attack on the military parade is likely to give security hardliners like the Guards more political ammunition because they did not endorse the pragmatist Rouhani's pursuit of the nuclear deal with the West, analysts say.
In New York, Trump's personal lawyer Rudy Giuliani said on Saturday that U.S. sanctions were inflicting economic pain on Iran that could lead to a "successful revolution". The Trump administration has said that changing Iran's system of government is not U.S. policy.
U.S. Secretary of State Mike Pompeo told Fox News on Sunday that Trump was willing to meet top Iranian officials for talks. Asked if Trump would like to meet with Supreme Leader Ayatollah Ali Khamenei, the highest authority in Iran, Pompeo replied: "The president has said he'll talk with anyone if we can have a constructive conversation."
Mostly Shi'ite Muslim Iran is at odds with Western-allied Sunni Muslim Saudi Arabia for predominance in the Middle East. The regional superpowers support opposing sides in the civil wars in Yemen and Syria, as well as rival political groups in Iraq and Lebanon.
A senior United Arab Emirates official denied Iranian allegations alluding to the involvement of the UAE in training gunmen that claimed the attack. The "formal incitement against the UAE from within Iran is unfortunate, and has escalated after the Ahvaz attack," Minister of State for Foreign Affairs for the United Arab Emirates Anwar Gargash said in a tweet.
Iran summoned the envoys of the Netherlands, Denmark and Britain on Saturday night over the shooting, accusing them of harbouring Iranian opposition groups in their countries. Some members of the ethnic separatist movements are based in the European countries.
Iranian foreign ministry spokesman Bahram Qasemi said Iran "asked their governments to condemn the attack and extradite people linked to it to Iran to be put on trial."
"It is not acceptable that these groups are not listed as terrorist organizations by the European Union as long as they have not carried out a terrorist attack in Europe," Qasemi was quoted as saying by IRNA news agency.
The Islamic Revolutionary Guards Corp (IRGC) has been the sword and shield of Shi'ite clerical rule in Iran since its 1979 Islamic Revolution. The Guards have a big say in Iran's regional interests and a vast stake worth billions of dollars in Iran's economy.
A video distributed to Iranian media showed soldiers crawling to escape gunfire. One picked up a gun and scrambled to his feet as women and children fled for their lives.
State television's website featured a video showing confused soldiers. Standing in front of the stand, one asked: "Where did they come from?" Another responded: "From behind us."
Ahvaz is in the centre of Khuzestan province, where there have been sporadic protests by minority Arabs.
Iran and Saudi Arabia support opposite sides in wars in Syria and Yemen and rival political parties in Iraq and Lebanon, fuelling instability in the Middle East. The attack occurred a day before Iranian President Hassan Rouhani heads to New York to address the annual United Nations General Assembly next week.
On his Instagram account, Rouhani said: "Those who are supporting these terrorists will be held responsible."
Iranian analysts said the attack may benefit the Guards. "Rouhani will use the terrorist attack to justify Iran's presence in the Middle East ... The attack will strengthen the IRGC's position inside Iran and in the region," Tehran-based political analyst Hamid Farahvashian said.
Iran faces pressure to swiftly respond to the high-profile attack, which has hurt the security establishment's prestige. "The attacks are doubtlessly meant to tarnish the prestige of the IRGC, but I believe the terrorist incidents will strengthen the IRGC's standing and even mobilise some public support," said Ali Alfoneh, senior fellow at the Gulf Arab States Institute in Washington.
Hardliners like the IRGC have gained standing at the expense of pragmatists in Iran's multi-tiered leadership since President Donald Trump decided in May to pull the United States out of the 2015 international nuclear deal with Tehran and re-impose sanctions on the Islamic Republic. "The United States stands with the Iranian people and encourages the regime in Tehran to focus on keeping them safe at home," said National Security Council spokesman Garrett Marquis.
Egypt, a key ally of Saudi Arabia, also condemned the attack.
Kurdish militants killed 10 Revolutionary Guards in an attack on an IRGC post on the Iraqi border in July. Last year, in the first deadly assault claimed by Islamic State in Tehran, 18 people were killed at the parliament and mausoleum of Ayatollah Ruhollah Khomeini, founder of the Islamic Republic.
