Iran's president and the commander-in-chief of the Islamic Revolutionary Guard Corp on Friday vowed revenge at the funeral for the victims of twin Islamic State bombings two days earlier.

Nearly 100 people were killed at a memorial in the city of Kerman on Wednesday for top commander Qassem Soleimani, who was assassinated in Iraq in 2020 by a U.S. drone.

Islamic State said on Thursday that two of its members had detonated explosive belts in the crowd that had gathered at the cemetery in the southeastern city.

"We will find you wherever you are," IRGC commander Major-General Hossein Salami said at the funeral, referring to Islamic State.

In a televised speech, President Ebrahim Raisi said: "Our enemies can see Iran's power and the whole world knows its strength and capabilities. Our forces will decide on the place and time to take action".

State TV showed a dense crowd at the Imam Ali religious centre in Kerman where families wept over rows of coffins wrapped in the Iranian flag.

Mourners shouted "revenge, revenge", "Death to America" and "Death to Israel".

Tehran often accuses Israel and the United States of backing anti-Iran militant groups that have carried out attacks in the past.

Wednesday's blasts, the bloodiest since the 1979 Islamic Revolution, came as Israel's war against Hamas in Gaza nears the three-month mark.

In 2022, Islamic State claimed responsibility for a deadly attack on a Shi'ite shrine in Iran that killed 15 people, while earlier attacks claimed by Islamic State include twin bombings in 2017 that targeted Iran's parliament and the tomb of the Islamic Republic's founder, Ayatollah Ruhollah Khomeini. REUTERS