TEHRAN — Iran's Supreme Leader Ayatollah Ali Khamenei has vowed a "harsh response" to a bomb attack on crowds marking the anniversary of spymaster Qasem Soleimani's assassination by the US.

The attack in Kerman in southern Iran killed 84 people and wounded many more.

The death toll was revised down on Thursday morning by the head of Iran's emergency services from an earlier figure of 95.

No group has yet claimed responsibility for the attack.

"Cruel criminals must know that they will be strongly dealt with from now on and undoubtedly there will be a harsh response," Khamenei said in a statement on Wednesday evening.

President Ebrahim Raisi's political deputy, Mohammad Jamshidi, blamed Israel and the US. However the US said it had no indication that Israel was involved and dismissed any suggestion that Washington was involved.

Suspicion may also fall on hardline groups like Islamic State (IS), who have carried out attacks on civilians and security forces in the country in recent years.

At the time, IS welcomed the death of Iranian general Qasem Soleimani, whose militias fought against the group in Iraq for years.

Soleimani was seen as the most powerful figure in Iran after the supreme leader before he was killed in a US drone strike in neighboring Iraq in 2020.

Wednesday's attack comes amid heightened tensions in the region after the deputy leader of the Iran-backed Palestinian group, Hamas, was killed in an apparent Israeli drone strike in Lebanon.

Footage broadcast by Iranian state TV showed large crowds were taking part in a procession along a road lined with banners featuring Qasem Soleimani when the explosions happened.

People could be heard screaming and then seen running away in panic after one of the blasts.

Iranian media reported the first bomb was detonated around 15:00 local time (11:30 GMT), about 700m (2,300ft) from the Garden of Martyrs cemetery around the Saheb al-Zaman mosque, in the eastern outskirts of Kerman.

The second bombing took place about 15 minutes later, around 1km away from the cemetery, targeting people who had fled the first, they said.

Kerman province's governor told state news agency Irna that both blasts happened outside security checkpoints and that authorities were sure they were caused by bombs. But he said it was not yet clear whether they were detonated remotely or by suicide attackers.

The hardline Tasnim news agency, which is affiliated with Iran's Revolutionary Guards, earlier cited sources as saying that "two bags carrying bomb" were apparently detonated "by remote control".

"We were walking towards the cemetery when a car suddenly stopped behind us and a waste bin containing a bomb exploded," a witness was quoted by Isna news agency as saying.

"We only heard the sound of the explosion and saw people falling."

The Iranian Red Crescent said the dead included at least one paramedic who was sent to the scene of the first explosion and was hit by the second.

Interior Minister Ahmad Vahid said the second blast killed and wounded the most people, and that an investigation had been launched to determine who was behind the attack.

President Ebrahim Raisi called the bombings a "cowardly act" carried out by "Iran-hating criminals and the henchmen of terror and darkness".

The former British ambassador to Iran, Rob Macaire, told the BBC that it was not clear who was behind the bombings.

"There are clearly opposition groups who have the ability, albeit quite constrained, to carry out violent attacks," he said. "I don't think they are regime-threatening attacks, but it will certainly raise the temperature."

UN Secretary General António Guterres strongly condemned the attack and expressed his "deep condolences to the bereaved families and the people and the government" of Iran, his spokesman said.

The EU said it condemned the bombing "in the strongest terms" and expressed its "solidarity with the Iranian people", while Russian President Vladimir Putin called the attack "shocking in its cruelty and cynicism".

Several Gulf countries, and Turkey, condemned the attacks while China's President Xi Jinping sent a message of condolence to the Iranian president.

The leader of Lebanon's Hezbollah movement - a powerful armed group that like Hamas is backed by Iran - said the victims were "martyrs who died on the same road, cause and battle that was led by" Soleimani.

As commander of the Revolutionary Guards' overseas operations arm, the Quds Force, Soleimani was an architect of Iranian policy across the region.

He was in charge of the Quds Force's clandestine missions and its provision of guidance, funding, weapons, intelligence, and logistical support to allied governments and armed groups, including Hezbollah and Hamas.

Then-US President Donald Trump, who ordered the 2020 drone strike, described Soleimani as "the number-one terrorist anywhere in the world" and alleged that troops under his command had murdered hundreds of American civilians and servicemen over the previous two decades.

Iran's government accused the US of an act of international terrorism and issued arrest warrants for Mr Trump and other officials. — BBC