Iran has arrested a large number of people, including senior intelligence officers, military officials and employees of a military guesthouse in Tehran, the New York Times reported.
The arrests are in response to information that the Israeli spy agency "Mossad" hired security agents from Iran's Islamic Revolutionary Guard Corps to plant explosives in three rooms of a Tehran compound, killing the head of "Hamas" Ismail Hania.
"The perception that Iran can neither defend its homeland nor its key allies could be fatal for the Iranian regime because it essentially signals to its enemies that if they cannot topple the Islamic Republic, they can they are beheading her," said Ali Vaez, the Iranian director of the International Crisis Group.
The investigation has been taken over by the Revolutionary Guard Corps' specialized espionage intelligence unit, with suspects being pursued in the hope they will lead them to members of the team that planned, aided and abetted Hania's murder.
News of the mass arrests came after the Revolutionary Guards said in a statement that "the scope and details of this incident are under investigation and will be announced in due course.
The National Guard has not yet released details of the arrests or the investigation into the explosion, including its causes. The intensity and scope of the investigation reveal the extent to which the murder shocked and shook the country's leadership.
According to political analyst Sasan Karimi, this security breach requires different policies and strategies.
Two Iranians familiar with the investigation said that after the attack, Iranian security agents raided the guesthouse complex, which is owned by the Revolutionary Guard Corps and where Haniya often stayed on visits to Tehran.
p>Agents have placed all guest house staff members under quarantine, arrested some and confiscated all electronic devices, including personal phones.
A separate team of agents interrogates senior military and intelligence officials with roles in guarding the capital. According to the two Iranians, a number of them have been placed under arrest pending the completion of the investigation.
The investigation has also focused on Tehran's international and domestic airports, where agents have been deployed to review records going back months, and to request flight lists. According to the Guards Corps, Chania's killers are still in the country.
An Iranian member of the Revolutionary Guard, who spoke on condition of anonymity because he was not authorized to speak, said he was not aware of the arrests but said security protocols had been completely overhauled in the past two days for senior officials. The security details of senior officials were changed and electronic equipment such as mobile phones were exchanged. He explained that some senior officials had been transferred to another location.
Iran's former president, Hassan Rouhani, who served in senior security positions, said in a statement that with the killing of the leader of "Hamas" Israel has also "targeted Iran's security and stability at the start of the new government" and added that the way to counter the threat is for all security, intelligence and military services to cooperate and strengthen their capabilities.