Deadly blasts have rattled Iran. As accusations fly, here’s what to know

ISIS has claimed responsibility for the deadliest attack in Iran since its 1979 Islamic Revolution, which has shaken the Islamic Republic and led to angry calls for vengeance.

On Wednesday, at least 84 people were killed and 284 others injured in the Iranian city of Kerman after twin blasts near the burial site of slain military commander Qasem Soleimani.

ISIS said Thursday that two bombers, who were brothers, had detonated their explosive vests as Shiite mourners gathered for the fourth anniversary of Soleimani’s assassination.

The claim punctuates a tense few days of uncertainty as speculation mounted on whether Israel’s war with Gaza would spread to other parts of the Middle East, potentially drawing in regional powers and the United States.

Here’s what we know about the attacks in Kerman:

What did ISIS say?

ISIS media wing Al-Furqan issued a statement, titled “And Kill Them Wherever You Find Them,” on Thursday as they claimed responsibility for the twin blasts.

They said that two brothers, who they named, set off towards a gathering of “polytheists” near the grave of their “dead leader” Qasem Soleimani, and detonated their explosive vests.

They also warned the “polytheists” that the “mujahideen are lying in wait for them and their projects.”

Islamic State considers the Shia branch of Islam to be heretical and has targeted shrines and religious sites in Iran previously.

The group offered no further proof and their account of the blasts differs from that given by Iranian media. The death toll provided by ISIS was also significantly higher than that reported by Iranian officials.

What are Iranian officials saying?

The first explosion was caused by a bomb placed in a suitcase in a car, and appeared to be detonated remotely, Iranian state television reported. The second, more deadly blast took place 20 minutes later, when people came to help the injured.

No one claimed responsibility for the attack for more than 24 hours, during which time Iranian officials were quick to blame Israel and said it will pay for it.

On Wednesday, the Israeli military told CNN it had “no comment” on the explosions. Israel does not usually respond to allegations that it carried out operations against Iranian interests. Also on Wednesday, US State Department spokesperson Matt Miller told reporters the department had “no reason to believe that Israel was involved.”

Some Iranian figures were skeptical. “Washington says USA and Israel had no role in terrorist attack in Kerman, Iran. Really?” Mohammad Jamshidi, Raisi’s Deputy Chief of Staff for Political Affairs, wrote on X, formerly Twitter.

Iran and Israel are bitter enemies. Iran backs anti-Israel groups like Hamas and Hezbollah, while Israel has vowed to prevent Tehran from getting a nuclear bomb and is accused by Iran of carrying out attacks to disrupt its nuclear program.

On Thursday, US State Department spokesperson Matt Miller said that the US was aware of reports that ISIS had claimed responsibility, but said he was “not ready to offer a formal assessment.”

He added that “this attack does bear all the hallmarks of an ISIS attack,” reiterating other US officials.

Iran has yet to respond to the ISIS claim as of Thursday but both Iran’s official state news agency IRNA, as well as its English-language state media outlet Press TV, reported on ISIS’s claim of responsibility.

Does Iran have many adversaries?

ISIS is one of several adversaries the Islamic Republic has aside from Israel. These includes Iranian opposition and separatist groups inside the country and out.

It faces separatist movements in the Sistan-Baluchestan province that borders Pakistan as well as Arab separatists in the Ahvaz province that borders Iraq, both of which are alleged to have carried out terrorist attacks in the country in recent years.

Iran has also come under attack by ISIS and its affiliates several times in the past decade.

Iran’s most prominent exiled opposition group is the Mujahedin-e-Khalq, which Tehran accuses Saudi Arabia of backing. But that organization is not known to have committed terrorist acts inside Iran in years, and Saudi Arabia’s relationship with Iran has improved significantly since last year.

Ali Vaez, a senior adviser at the International Crisis Group, a Brussels-based think tank, wrote on X that if Israel was behind the attack, it would be part of a campaign of maximum provocation “to prompt Iran into committing a mistake that would justify expanding the war (with Hamas) and dragging the US in.”

But he added that the attack didn’t bear the hallmarks of an Israeli operation, but rather those of ISIS or Baluchi separatists.

Past attacks that Iran has blamed on Israel have typically targeted individuals, rather than larger groups of people, or facilities tied to to the regime’s nuclear program. Several nuclear scientists have died in targeted killings over the past decade. Mohsen Fakhrizadeh, Iran’s chief nuclear scientist, was one of the highest-profile officials to be killed, in 2020. In 2021, Iran reported a blackout at the Natanz nuclear facility where uranium enrichment takes place, and blamed it on Israel. Israel neither confirmed nor denied involvement in either attack.

A senior White House official told reporters Wednesday that the blasts “look like a terrorist attack.” The official added that the attacks are “the type of thing we’ve seen ISIS do in the past” and that is “our going assumption at the moment.”

ISIS and Khorasan group, a branch of ISIS in Afghanistan, have a history of terrorist attacks in Iran and they tend to try and inflict higher civilian casualties, said Sanam Vakil, deputy head of the Middle East North Africa program at the Chatham House think tank in London.

Where does this fit in the regional situation?

The blast in Kerman occurred amid heightened tensions in the region as Israel fights a three-month war against Hamas in Gaza prompted by the militant group’s October 7 attack on Israel.

That war has led to skirmishes beyond Israel and Gaza, often involving Iran-backed militias.

In Lebanon, a senior Hamas leader was killed on Tuesday in a suburb of Beirut in a blast that a US official told CNN was carried out by Israel. Israel hasn’t confirmed or denied involvement but Hamas and the Iran-backed Lebanese group Hezbollah, which controls the suburb, blamed Israel and both have vowed revenge.

In Syria, Iran and several of its armed proxies accused Israel last week of assassinating senior Iranian commander Seyyed Razi, vowing retaliation. Israel didn’t comment on the matter.

Israel accuses Tehran of funding and arming Hamas. Israeli Defense Minister Yoav Gallant said last month that his country is in a “multi-arena war,” being attacked from seven arenas, including Iran. “We have already responded and acted in six of these decrees” he said.

And in Iraq, a commander of a group in the Iran-backed Popular Mobilization Front (PMF) was killed on Thursday in an unidentified strike on their base in East Baghdad, a source with the PMF told CNN.

Mushtaq Talib Al-Saadi, the commander also known as Abu Taqwa, was killed after his vehicle was targeted as he was entering the logistical support headquarters of Harakat al-Nujaba – an Iranian proxy operating in Iraq and Syria – the PMF source said. His assistant, Abu Sajjad, was also killed in the attack.

A US official told CNN that the US had targeted a member of Harakat al-Nujaba. The official said the US had been watching the individual for some time before the strike and that he had “US blood on his hands.”

How is Iran likely to respond?

Anger was already simmering in Iran over the killing of Mousavi . The Kerman attack adds to the Iranian government’s embarrassment, showing that not only is it unable to keep alive some of its top officials, but it also can’t prevent attacks on home soil.

The regime may now be under increased pressure internally to punish the perpetrators.

On Thursday, a billboard was unveiled on Tehran’s main square with the words: “Strong answer, God willing,” apparently calling on the government to respond harshly to the Kerman attack.

Tehran had blamed Israel for the attack but it is unclear what the calculus is now that ISIS has claimed responsibility.

Iran has reportedly plotted to kill Israelis in Europe and Asia in recent years in an effort to avenge Israel’s alleged operations against it, but it has failed. Right-wing critics of the Iranian government deem those attempts as insufficient retaliation for the killing of senior Iranian officials, Mohammad Mazhari wrote in a paper published by the Stimson Center, a Washington DC-based think tank.

“Iranian officials are confused and divided regarding the appropriate method of exacting revenge,” Mazhari wrote ahead of the killing of Mousavi. “Their relative inaction is in line with a policy of strategic patience that seeks to avoid a direct confrontation with the US or Israel.”

Tehran is in an awkward position, said Vakil. “Pointing the finger at terror groups will provide Iran with a way out of this pressure,” she said. “It can blame Israel and the US for stoking regional unrest, but blame IS to avoid taking action.”

Barbara Slavin, a fellow at the Stimson Center, told CNN’s Becky Anderson on Wednesday that Iran hasn’t been retaliating to attacks against it in a timely fashion “which raises the question… whether there’s concern about internal stability in the country.”

In late 2022, Iran was rocked by some of the biggest protests since the Islamic Revolution in 1979, prompted by the death of a young woman at the hands of the country’s so-called morality police. Those protests were brutally crushed.

“All in all, the Kerman attack has once again highlighted Iran’s vulnerability and the government’s failure in providing security,” Vaez wrote on X. “While the security forces seem adept at harassing women not wearing hijab, they fail to save their lives and protect them against terrorism.”

CNN’s Samantha Waldenberg and Mostafa Salem contributed to this report.

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