The funeral of the murdered Mohsen Fakhrizadeh was held today in Tehran.
At the same time as Israel was singled out as guilty of the assassination, the demands for revenge are now being raised.
But in Iran, there is a tug-of-war between pragmatists and hawks over how and when Iran should respond to the assassination.
Remote machine gun
Fakhrizadeh, who has been called the father of the Iranian nuclear program, and who has been repeatedly singled out by Israel and the United States for leading a secret nuclear weapons program, was shot dead in an advanced ambush on a highway outside Tehran on Friday night.
According to Iranian media, the fatal shots were fired by a remote-controlled machine gun mounted on an unmanned vehicle.
Father's TV reports that Fakhrizadeh and his wife were traveling in a bulletproof vehicle in a convoy of armored vehicles east of Tehran on Friday when gunfire was heard.
When Fakhrizadeh drove into the roadside to check that his car was not damaged, the shots were fired from the remote-controlled machine gun.
One of the bullets must have hit the nuclear physicist in the back.
Raises demands for revenge
Tehran denies having a nuclear weapons program.
But the fact that the attack took place on Iranian soil, less than a year after the high-ranking General Qassem Soleimani was killed by the United States, distorts the feeling of vulnerability, and the cry for powerful revenge.
Sources in the US intelligence service tell the New York Times that Israel is behind the attack.
The Israeli security service Mossad is suspected of having killed several Iranian nuclear physicists in the last decade.
Israeli ministers officially say they "have no idea" about the incident.
President Hassan Rouhani has said that Iran will demand revenge "enough time" - while more stubborn voices call on the regime to strike at the Israeli city of Haifa.
"It will definitely be a deterrent because neither the United States nor the Israeli regime and its agents are ready for war and a military confrontation," the state-run Kayhan newspaper wrote.
At the same time, one of the motives behind the assassination could be to trigger an advanced act of revenge, as it could complicate new talks between the United States and Iran.
Biden can change the relationship
In just over seven weeks, a new president will take office in the White House.
The biggest change in US foreign policy under Joe Biden is predicted to be the relationship with Tehran.
Biden has said he is open to returning to the international nuclear deal with Iran, if the country fulfills its commitments.
Tensions between Tehran and Washington have risen since President Donald Trump left the nuclear deal two years ago.
New sanctions have hit Iran's economy hard.
In recent times, Iran has responded by gradually violating the rules of the nuclear agreement.
Tehran Parliament now calls for an end to international inspections of its nuclear facilities.
There is no doubt that the assassination of Mohsen Fakhrizadeh was carried out in an extremely sensitive time.