Two explosions killed at least 103 people and wounded 171 others near a cemetery during a ceremony honouring Iran's top commander Qassem Soleimani, who was killed by a US drone strike in 2020.
Iranian state television claimed many injuries from an explosion during the ceremony in the southeast city of Kerman.
The Deputy governor of Kerman stated that it was a "terrorist attack".
"Several petrol canisters exploded on the road leading to the cemetery and relevant authorities are monitoring the situation," stated the semi-official Nournews.
According to the SNN news agency, ambulances were spotted drawing near the cemetery, where hundreds of Iranians had come to mark the anniversary of Soleimani's death.
After Ayatollah Ali Khamenei, the Supreme Leader of Iran, Soleimani was regarded as the most powerful person in the country.
He was a key figure in shaping Iranian policy throughout the region as the head of the Quds Force, the Revolutionary Guards' branch for international operations.
He was in command of the covert operations of the Quds Force and its provision of advice, capital, armaments, information, and logistical assistance to ally governments and armed organisations, such as Hezbollah and Hamas.
Soleimani was referred to as "the number-one terrorist anywhere in the world" by then-US President Donald Trump, who gave the order for the 2020 murder.
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