Shafaq News/ The Israeli Mossad assassinated Hamas political leader Ismail Haniyeh by detonating an explosive device planted in his bedroom at the Iranian government official residence in Tehran, two sources with knowledge of the issue confirmed to Axios.

The fact that the Mossad managed to plant the explosive device in a high-security facility demonstrates the deep penetration of Israeli intelligence services inside Iran and the vulnerabilities of the Iranian intelligence and security apparatus.

The details about the planted explosive device were first reported by The New York Times and confirmed to Axios by two sources.

The explosion that killed Haniyeh took place on Tuesday night, but the official announcement of his assassination was published several hours later on Wednesday morning. The initial statement from Hamas claimed Haniyeh was killed in an Israeli airstrike. Iranian media initially reported that three missiles were launched by a drone, later stating the missile was launched from outside Iran.

Sources said Israeli intelligence learned which facility and exact room Haniyeh stayed in during his visits to Tehran. The bomb, a high-tech device utilizing artificial intelligence, was planted in the room in advance and detonated remotely by Mossad operatives on Iranian soil after confirming Haniyeh's presence in the room.

The Islamic Revolutionary Guard Corps (IRGC) has opened an investigation into the incident. Israel did not inform the U.S. or any other ally in advance of the assassination, according to Axios, but Israeli officials briefed their U.S. counterparts on the details of the operation on Wednesday evening.

Rear Adm. Daniel Hagari, a spokesperson for the Israeli military, stated in a press briefing on Thursday that there was no Israeli airstrike or missile attack in the Middle East on Tuesday night other than one in Beirut. He also claimed that Iran has been working on smuggling sophisticated explosive devices to groups in the West Bank over the past year.

Israeli Prime Minister Benjamin Netanyahu, who oversees the Mossad, made the decision to assassinate Haniyeh. Sources indicated that negotiations to release hostages held by Hamas in Gaza and establish a ceasefire were factors in the decision-making process. One source said the Mossad believed Haniyeh's assassination would bring justice to the Oct. 7 attack victims and remove an obstacle to the hostage deal, noting that Haniyeh had a more hardline view on the deal than Hamas leader in Gaza, Yahya Sinwar.

"Haniyeh presented a pragmatic face to the mediators but internally inside Hamas led a hard line," the source said.