Iranians Finger Mole In Nuclear Scientist Murders

VIDEO: Shahram Amiri claims the CIA kidnapped him but U.S. officials say he
WATCH Nuclear Scientist Returns to Iran

Iranian authorities are investigating the coworker of a nuclear scientist shot dead this summer for possibly leaking info about the scientist, according to the Associated Press. The dead scientist, Darioush Rezaeinejad, was the fourth scientist allegedly linked to Iran's nuclear weapons program killed by unknown assailants in the past four years.

According to the AP, an intelligence report by a member nation of the International Atomic Energy Agency says the Iranians think a specific colleague of the murdered scientist was linked to "unreliable elements," and might have been the source of a leak about Rezaeinejad. The IAEA report also says Rezaeinjad played a "key role" in Iran's nuclear program, and an IAEA official told the AP that Rezaeinejad was working on a trigger for a nuclear weapon.

The story of a mole comes as the Iranian envoy to the IAEA, now holding its meeting in Vienna, told reporters that his country would not retaliate against whoever is killing its nuclear scientists. "We want not only our scientists, we want all scientists of the world to be protected," said Iranian Ambassador Ali Asghar Soltanieh. He said he hoped both the IAEA and the United Nations would investigate the murders.

Since 2007, four different scientists allegedly associated with the nation's nuclear weapons program have died via bomb, gunshot or poisoning, while a fifth barely survived a car bombing. Iran has blamed the killings on Israel, the United States and Britain. The U.S. has denied any involvement, while the Israelis have declined comment.

Rezaeinejad, the most recent victim, was shot outside his daughter's Tehran kindergarten in July by two men on motorcycles. At the time, an unconfirmed report in an Israeli intelligence publication said that Rezaeinejad was working on a nuclear detonator and was seen daily at a nuclear lab in northern Tehran.

Rezaeinejad's murder sparked official outrage in Iran. State media quickly published an online report in which a leader of the nation's parliament said the killing showed the "desperation" of the U.S. and Israel.

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In most cases, Iranian officials blame the deaths and disappearances on the West without equivocation. In November 2010, a magnetic bomb placed by a motorcyclist killed nuclear physicist Majid Shahriari in his car. President Mahmoud Ahmadinejad quickly blamed "Western governments and the Zionist regime" for the twin bombings.

The same day, Fereydoon Abbasi, the head of Iran's Atomic Energy Organization was wounded when a motorcyclist detonated a magnetic bomb under their car by remote control. Abbasi was on a U.N. list of people sanctioned for suspected links to nuclear activities.

In Vienna on Monday, Abbasi himself blamed the U.S., Israel and the U.K. for his brush with death, claiming that British intelligence had followed him for six years and then entrusted the Israelis with the responsibility of killing him.

Did Mossad Kill Ardeshir Hassanpour?

Sometimes, however, Iranian officials will downplay the deaths, as if casting doubt on the ability of hated foes to strike at will. The same state website that published an article in July decrying the murder of Rezaeinejad as a Western assault on Iran's nuclear program published a second story ten minutes later saying his death really wasn't such a big deal after all. Iranian intelligence minister Heidar Moslehi was quoted saying it was unclear who killed Rezaeinejad and that he wasn't a nuclear scientist anyway. "The assassinated student was not involved in nuclear projects and had no connection to the nuclear issue."

In early 2007, Ardeshir Hassanpour, an Iranian nuclear scientist working at a nuclear plant in Isfahan, died from what Iranian state media called "gas poisoning." While the private U.S. intelligence firm Statfor reported that Mossad had killed Hassanpour, the Iranian government said that Hassanpour was not involved in nuclear research and had died in an accident.

Iranian opposition groups, meanwhile, say that sometimes the Iranian government kills dissident scientists -- who may or may not have anything to do with nuclear weapons -- and then blames the murders on the West.

In January 2010, a motorcycle parked outside the house of nuclear physicist Masoud Ali Mohammadi was detonated by remote control when he walked past.

The regime blamed his murder on a "triangle of wickedness," meaning the U.S., Israel and their "hired agents." "Zionists did it," said Ahmadinejad. "They hate us and they don't want us to progress."

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But Western intelligence agencies had conflicting information about whether Mohammadi, a particle physicist, was really contributing to the nuclear program. An Iranian opposition group said Mohammadi had been killed by the regime because he was a supporter of Mir Hossein Mousavi, whom many believe actually won the 2009 Iranian presidential election before vote-tampering handed the victory to Ahmadinejad. A German-based opposition group released a photo of an alleged Arab hitman who had supposedly carried out Mohammadi's assassination on regime orders.

U.S. Official: Murder Charges 'Absurd'

A former senior intelligence official involved in efforts to thwart Iran's nuclear program told ABC News that assassinations of top Iranian scientists were usually assumed to be the work of Israel, but that the Israelis would never confirm or admit responsibility.

"Every time we ask," said the official, "they just smile and say, 'We have no idea what you are talking about.' "

The U.S., for its part, has officially denied any involvement in the deaths of Iranian scientists. A White House spokesman called the accusations "absurd" after Mohammadi's death. The CIA is known, however, to have recruited scientists as spies.

In 2007, after Iranian General Ali-Reza Asgari went missing in Turkey, the Iranian government said the intelligence official had been kidnapped by Mossad. The Israeli and Western media said he had defected, and was busy providing information on Iran's nuclear program.

Two years later, award-winning Iranian nuclear scientist Shahram Amiri disappeared while on a pilgrimage to Mecca. He later resurfaced in the United States after defecting to the CIA in return for a large sum of money, according to people briefed on the operation by intelligence officials. A spokesperson for the CIA declined official comment.

Amiri, a nuclear physicist in his early 30s, worked at Tehran's Malek Ashtar University, which is closely connected to Iran's Revolutionary Guard, according to the AP.

When Amiri disappeared, Iran's Foreign Minister, Manouchehr Mottaki, and other Iranian officials blamed the U.S. for "kidnapping" Amiri.

After resurfacing in the U.S., Amiri released two videos, one in which he claimed he was kidnapped by the CIA, and another in which he denied he was kidnapped. He later repeated the kidnapping story publicly, said he had "escaped" from the CIA, and returned to Iran.

In January 2011, a dissident website reported that Amiri was being held in a Tehran prison and had been tortured.

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