Iran has started a thorough inquiry into Ismail Haniyeh’s murder; the probe’s rigor indicates how devastating and startling the security lapse was.

According to two Iranians familiar with the investigation, Iran has detained over twenty-six people, including military officials, staff members at a guesthouse run by the Iranian military, and senior intelligence officers, in response to a significant and embarrassing security lapse that allowed for the assassination of a senior Hamas figure.
The high-level arrests followed the early Wednesday blast that killed Ismail Haniyeh, the leader of Hamas’s political office in Qatar, while he was in Tehran for the new president of Iran’s inauguration. Haniyeh was staying at a guesthouse in the city’s north.

Given that Mr. Haniyeh was killed at a tightly secured facility in the nation’s capital only hours before the new president of Iran was sworn in, the intensity of the outcry following his death highlights just how grave a security blunder this was for Iran’s authorities. According to Ali Vaez, the director of the International Crisis Group’s office in Iran, “the perception that Iran can neither protect its homeland nor its key allies could be fatal for the Iranian regime, because it basically signals to its foes that if they can’t topple the Islamic Republic, they can decapitate it.”
According to officials in Iran and the Middle East, Mr. Haniyeh’s room contained a bomb that had been hidden there up to two months before to his arrival, which is what caused the terrible explosion.
A number of U.S. officials also came to the same conclusion on Wednesday: Israel was the cause of the assassination, according to Hamas and Iranian authorities. Israel has not admitted that it planted the bomb, despite its commitment to undermine Hamas’s political and military capabilities.
The two Iranian officials, who asked to remain anonymous due to the sensitive nature of the investigations, said that the Revolutionary Guards Corps’ special intelligence unit for espionage has taken over the investigation and is searching for suspects that it hopes will lead it to members of the assassin team that planned, assisted, and carried out the killing.
The Revolutionary Guards declared in a statement that “the scope and details of this incident are under investigation and will be announced in due course.” This announcement before reports of the mass arrests.