TEHERAN / GAZA - Iran's Islamic Revolution Guards Corps (IRGC) said on Saturday that Hamas Politburo Chief Ismail Haniyeh was assassinated by a "short-range projectile loaded with an almost 7-kg warhead."

"In view of the conducted investigations, the terrorist operation has been carried out through firing from outside the guests' residence a short-range projectile loaded with an almost 7 kg warhead, causing an intense explosion," the IRGC said in its third statement about Haniyeh's assassination in an alleged Israeli attack in the Iranian capital Teheran, according to the armed force's official news outlet Sepah News.

ALSO READ: Hamas vows killing of leader ‘will not go unpunished’

The statement added the "terrorist" attack had been designed and carried out by Israel with the US government's support.

The IRGC stressed that "the revenge for Haniyeh's blood will be definite," adding the "adventurist and terrorist" Israel would receive a "decisive response to this crime, which is a harsh punishment, at the appropriate time and place and with the appropriate quality."

Haniyeh, who had been invited to attend the swearing-in ceremony of Iranian President Masoud Pezeshkian on Tuesday, was killed along with his bodyguard early Wednesday when their residence in Teheran was hit.

Meanwhile, Hamas said on Saturday that wide consultation has started in its leadership and consultative institutions to choose a new chief for the movement.

READ MORE: Iran's supreme leader vows to avenge Hamas chief's death in Teheran

Past decades witnessed the killing of a number of its leaders, but the group was quick to choose alternatives to them in accordance with the regulations of the movement, Hamas said in a statement.

The movement's executive institutions and its Shura, the main consultative body, are continuing their work, and it will announce the results of its consultations once they are completed, the statement said.