The assassination of Hamas leader Ismail Haniyeh appears to have been a premeditated event with months of careful planning. Recent reports contradict Iranian claims that the top official was killed during a pre-dawn airstrike on Wednesday. It has now been suggested that Israeli intelligence agency Mossad recruited members of the Iranian Revolutionary Guards to plant a bomb in his temporary residence.

Reports by The New York Times, Axios, and the Wall Street Journal indicate that the the Hamas chief was killed by a bomb in his apartment that was planted weeks — or perhaps even months — ahead of his arrival in Tehran. Haniyeh was in Iran for the inauguration of Iranian President-elect Masoud Pezeshkian. His predecessor (Ebrahim Raisi) was incidentally killed in a helicopter crash earlier this year — with many pointing fingers at Israel.

The assassination plan appears to have been formulated soon after the death of Raisi. According to a report by The Telegraph, the initial plan was to assassinate Haniyeh as he attended the funeral in May. The British daily however cited two Iranian officials as saying that the operation was later called off due to the large number of people in the building and the possibility of failure.

“Instead, the two agents placed explosive devices in three rooms of the Islamic Revolutionary Guard Corp guesthouse in north Tehran where Haniyeh might stay. The agents were seen moving stealthily as they entered and exited multiple rooms within minutes, according to the officials who have CCTV footage of the building,” The Telegraph report added.

The bombs were reportedly detonated from abroad. Officials quoted by the publication also claimed with near certainty that Mossad had “hired agents from the Ansar al-Mahdi protection unit” to carry out the attack. The IRGC unit in question is responsible for ensuring the safety of high-ranking officials.

(With Inputs From Agencies)