Originally Published: 03 JAN 24 07:58 ET

Updated: 03 JAN 24 11:25 ET

By Mostafa Salem, Abbas Al Lawati and Rob Picheta, CNN

(CNN) — At least 103 people were killed Wednesday and 141 injured in the Iranian city of Kerman after twin blasts near the burial site of slain military commander Qasem Soleimani, in what officials called a terror attack.

The blasts, at least one of which was caused by a bomb, state TV said, came on the fourth anniversary of Soleimani’s death in a US air strike, and threatens to accelerate tensions in the region that have spiked since the start of the Israel-Hamas war in Gaza.

The first explosion was 2,300 feet (700 meters) from Soleimani’s grave, and the second was 0.6 miles (1 kilometer) away as pilgrims visited the site, IRNA added.

Soleimani was killed by a US airstrike ordered by former President Donald Trump at Baghdad International Airport four years ago Wednesday.

IRINN, another state television channel, reported that the first explosion near the grave of Soleimani was caused by a bomb placed in a suitcase inside a Peugeot 405 car, and appeared to be detonated remotely.

Iran’s Interior Minister Ahmad Vahidi said the first explosion happened at 3:00 p.m. local time (6 a.m. ET) during an interview with Iran’s state news channel IRIB. Vahidi said the second, more deadly blast took place 20 minutes later, when other pilgrims came to help the injured.

No group has yet claimed responsibility for the blasts.

Videos posted on Iranian state media showed large crowds running in the area after the explosion.

Footage also showed bloodied bodies being transported from the scene, and ambulances leaving the site through large crowds.

Iran declared Thursday a day of mourning following the blasts.

Formerly one of Iran’s most powerful men, Soleimani was head of the Revolutionary Guards’ Quds Force, an elite unit that handles Iran’s overseas operations and was deemed to be a foreign terrorist organization by the US.

The Pentagon says Soleimani and his troops were “responsible for the deaths of hundreds of American and coalition service members and the wounding of thousands more.”

Known as Iran’s “shadow commander,” Soleimani – who had led the Quds Force since 1998 – was the mastermind of Iranian military operations in Iraq and Syria.

Blast comes at tense moment in region

The blast 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 left more than 23,000 people dead in Gaza, according to the Hamas-run Ministry of Health in the enclave, and has led to skirmishes beyond Israel and Gaza, often involving Iran-backed militias.

On Tuesday, a senior Hamas leader was killed 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 militant group Hezbollah, which controls the suburb, blamed Israel and have vowed revenge.

Hezbollah’s leader Hassan Nasrallah is set to deliver a speech on Wednesday, his third since the war broke out. The speech was announced before the Beirut attack.

Last week, Iran and several of its armed proxies accused Israel of assassinating a senior Iranian commander in Syria, 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.

On Wednesday, Russian President Putin condemned “terrorism in all its forms” in a letter to Iran’s Supreme Leader Ayatollah Ali Khamenei and President Ebrahim Raisi after the blasts. Putin, who is the subject of an arrest warrant from the International Criminal Court, has been accused by Kyiv and international bodies of numerous acts of terror during his war in Ukraine.

The United States has also stepped up its military involvement in the Middle East recently. Last month, the military carried out airstrikes on Iranian-backed Kataib Hezbollah and “affiliated groups” in Iraq after an attack injured three US troops.

And last week, US helicopters sank three boats belonging to Iran-backed Houthi rebels in the Red Sea after coming under fire, killing those on board. The event marked the first time since tensions broke out earlier last year that the US killed members of the rebel group.

The White House said it wasn’t seeking a wider conflict. The Houthis have carried out several attacks on merchant vessels in the Red Sea in retaliation for Israel’s assault on Hamas, disrupting trade in one of the world’s most important waterways.