Mostafa Ahmadi Roshan is the fifth Iranian scientist to become the target of terrorist operations. He was a professor of physics at Sanati Sharif University in Tehran and deputy director for commercial affairs at Natanz nuclear plant .

According to Iranian media, the physicist was killed in a terrorist attack near the Ministry of Intelligence headquarters, and Iran’s political and security officials have attributed the assassination to Western countries and, specifically, Israel.

The head of the Tehran Provisions Council told Fars News Agency: “The assassination of Ahmadi Roshan was carried out by the Israeli intelligence service.” He claims that in the lead-up to Iran’s parliamentary elections in March, Western intelligence services are trying to provoke a security clampdown that will discourage people from going out in public during the elections.

Mohammad Esmail Kosari, a Tehran representative in Parliament and a member of the National Security Commission, told Fars News Agency: “Ahmadi Roshan’s assassination is completely targeted and similar to the assassination of Shahriyari.” He also insists that Western countries and Israel are trying to stop Iran’s advance in nuclear science.

Such official accusations against foreign countries, however, follow previous efforts to attribute the assassinations to domestic opposition groups or unexpected accidents.

The mysterious death of the centrifuge designer

The first Iranian physicist killed in the past five years was Ardeshir Hosseinpour, who had a PhD in Physics and was a professor at Malek Ashtar University. He was killed in February of 2007, and the cause of his death was reported in the media as inhalation of fumes from a gas leak.

Iranian security forces and Iran’s Atomic Energy Agency made every effort to conceal the news of his death, but five days after the incident, Iran’s national broadcaster reported on the mysterious fate of the Malek Ashtar and Shiraz University professor.

While Iran’s Atomic Energy Organization denied any links between Hosseinpour and Iran’s nuclear program, the Baztab website, run by former Revolutionary Guards commander and secretary of the Expediency Council Mohsen Rezai, announced that Hosseinpour was a designer of nuclear centrifuges.

According to this report, Hosseinpour was in charge of 12 top defence projects, including the propulsion motors for Shahab 3 missiles.

At the time of Hosseinpour’s death, The Sunday Times of London quoted the Texas-based private intelligence company Stratfor, saying that Hosseinpour was connected with Iran’s nuclear project and had been poisoned by radioactive gases.

The report also quoted the company saying that the Iranian scientist was probably targeted by Israeli intelligence services.

Russia’s Novosti News Agency reported that Hosseinpour could have been the father of Iran’s atomic bomb and speculated that he might have been assassinated by the Mossad.

However, five years ago, Iranian security and nuclear officials denied that Israel had any hand in Hosseinpour’s death and insisted that Western security agencies lack the capability to carry out such operations in Iran.

Iran’s official media stuck to the story that Hosseinpour was killed by gas inhalation in the Shiraz University dormitory, though some indicated that he might have been poisoned during nuclear tests at the Natanz nuclear facilities.

Assassination of two physicists

Three years after the death of Ardeshir Hosseinpour, two simultaneous terrorist operations were carried out in Iran. One targeted Majid Shahriyari, another nuclear physics professor, this time at Shahid Beheshti University, and a designer of the configurations of the 20-percent-enriched fuel plates for nuclear centrifuges.

The attack claimed the life of Majid Shahriyari, who was described as Iran’s top nuclear scientist by the former head of Iran’s Atomic Agency and the current foreign minister, Ali Akbar Salehi. That same day, nuclear scientist Fereydoon Abbasi Davani was targeted in a separate assassination attempt, which he survived, and he now heads Iran’s Atomic Energy Organization.

Those two assassination attempts were quite different. Shahriyari was killed with a remote-control bomb, while Abbasi Davani was shot at while in his car.

This time, Iranian security officials accused Israel and the U.S. of carrying out the attacks, and Intelligence Minister Heydar Moslehi announced: “We have several clues as to who perpetrated the assassination attempts on our two top physicists.”

Iranian President Mahmoud Ahmadinejad attributed the assassinations to British intelligence services. Parliamentary Speaker Ali Larijani and MP Mohammad Esmail Kosari accused Israel and the U.S. The Fars News Agency maintained that the countries involved in nuclear negotiations with Iran were behind these terrorist operations.

Some analysts declared, however, that the attempt on Abbasi Davani’s life was staged, citing the differences between the two operations as ample proof of their allegations.

Massoud Ali-Mohammadi, professor and protester

A year before the double assassination attempts, at at time when the Islamic Republic regime was cracking down on demonstrations against the election results, Massoud Ali-Mohammadi, a physics professor at Tehran University, was killed in a terrorist attack in front of his home. While domestic and international media linked him to Iran’s nuclear dossier, that was denied by Ahmad Shirzad, a reformist MP in the sixth Parliament.

Iran’s Atomic Energy Agency also denied that Ali-Mohammadi was on staff there. However, Parliamentary Speaker Larijani described Ali- Mohammadi as a figure in Iran’s nuclear program and once again linked his death to Israel and the U.S.

A number of Iranian newspapers, however, reported that Ali-Mohammadi was a supporter of MirHosein Mousavi, the presidential candidate who had challenged Mahmoud Ahmadinejad’s victory in the 2009 presidential election, and added that he had been very vocal in his criticism of the government.

The assassination of Ali-Mohammadi spawned much speculation and several theories. The Islamic Students Society and Conservative MP Hamid Resai maintained that the election protests led to Ali-Mohammadi’s assassination, and some internet sites speculated that the government might have been involved in staging the attack. None of these statements was ever corroborated by any evidence.

The athlete that was presented as a terrorist

The Russian daily Kommersant and another Iranian analyst claimed that Ali-Mohammadi was indeed an Iranian nuclear scientist, and that it was possible his assassination had been carried out by Israeli security services. These statements were backed by pointing out similarities between Ali-Mohammadi’s assassination and the Israeli operation that targeted an Iraqi nuclear scientist.

Fars News Agency, however, said the dissident group Anjoman-e Padeshahi Iran was responsible for the attack, which the organization immediately denied.

Finally, a year after the assassination of this prominent professor, the Islamic Republic Intelligence Ministry announced that it had arrested Ali-Mohammadi’s killers.

Later, Iranian state television aired parts of the alleged confession of Farshid Jamali fash, in which he admitted having been trained by the Israeli intelligence service to assassinate Ali-Mohammadi.

Once Jamali fash was seen on television, it was discovered that he was a member of Iran’s national kickboxing team as well as Mahmoud Ahmadinejad’s election campaign.

While he claimed that he had assassinated Ali-Mohammadi on a mission from the Mossad, Israel denied any links between Jamali fash and its intelligence agency.

Daryoosh Rezainejad became the next member of Iran’s scientific elite to be killed in a terrorist attack. Domestic media first described him as a physicist connected with Iran’s nuclear program, but hours later this was denied, and it was announced instead that he had been working with the Ministry of Defence.

Iran once again accused Israel of carrying out Rezainejad’s assassination, maintaining that it had been mistaken in its target. Months after this incident, there has still been no information released about Rezainejad’s assassins.

Unknown Terrorists

Now, with the assassination of Mostafa Ahmadi Roshan, the subject of Iran’s targeted nuclear scientists has come into the spotlight once more. Iran has again accused Israel of perpetrating the act, and the Foreign Ministry spokesman is already making retaliatory statements.

A day after Ahmadi Roshan’s assassination, Hossein Shariatmadari, the managing director of the Keyhan daily, who is considered a direct conduit for the Supreme Leader’s views, criticized the government and the security services for failing to retaliate against the terrorist attacks.

In an editorial, Shariatmadari wrote: “One must ask why the Islamic Republic is not exercising its right to respond in kind, which is recognized not only in Islamic teaching but also in all the international legal systems under the section ‘Retaliate’?”

He added: “It is easily possible for the Islamic Republic’s intelligence and security services, which have become veterans of the all-out war with the intelligence and security forces of the enemy through 32 years of vast and complex experiences, to assassinate Israeli military and government officials.”

Israel has refrained from responding to the accusations regarding Ahmadi Roshan, but U.S. Foreign Secretary Hilary Clinton condemned the terrorist act and emphasized that her country had no role in the operation and condemns the murder of innocent people.

Javan-on-line, a website connected with the political bureau of the Revolutionary Guards, has claimed to possess several clues regarding Ahmadi Roshan’s assassination. It claimed that it is trying to identify the assailants using video captures from traffic cameras. Iran’s Intelligence Minister has also said the perpetrators will soon be announced.

The Islamic Iran Participation Front, a reformist opposition group that has been banned since the controversial protests against the disputed 2009 presidential election, has issued a statement addressing the terrorist attacks of the past three years, calling on the country’s security forces to concentrate on protecting Iranian scientists rather than arresting political activists and creating a security-laden atmosphere all across the country.

A  number of political activists have also urged the government to stop its nuclear adventurism and the sacrifice of Iranian professors and scientists on the altar of their erroneous policies.

Five years after the mysterious death of Ardeshir Hosseinpour, and with another four terrorist operations carried out since, Iran’s security forces have presented only one alleged perpetrator, Farshid Jamali fash, as the accused killer of Massoud Ali-Mohammadi, a crime they claim is linked to the Mossad.

Even this claim has been called dubious by several analysts and media outlets, and the public still awaits the real story behind the serial assassination of Iranian scientists.