An Iranian university professor killed last week by a blast from a remote-controlled bomb strapped to a parked motorcycle may have been the victim of an Arab hitman, according to opposition groups.

The murder of Masoud Ali Mohammadi, 50, a supporter of Mir Hossein Mousavi, the opposition leader, has been blamed by the Tehran regime on “mercenaries” financed by Israel and Washington because of his role as a nuclear physicist.

However, opposition groups who monitor Hezbollah, the militant Lebanese movement, in Tehran, claim that a member of the group, known by his pseudonym “Abu Nasser”, was photographed at the scene of the explosion in Tehran’s affluent Gheytarih suburb.

A German-based opposition group released a photograph of a man of similar appearance who, it alleges, was one of the pro-regime demonstrators who stormed Mousavi’s office in Tehran after disputed presidential elections last June.

The opposition claims the Revolutionary Guard uses Hezbollah operatives for some bloodthirsty tasks because they have a reputation for ruthlessness, and are outsiders and can always be blamed as opposition sympathisers.

Tehran has gone to great lengths to suggest that Mohammadi was killed because he was a nuclear scientist, implying that he was part of Iran’s program to develop nuclear weapons.

However, Majid Mohammadi, a visiting scholar at the Institute for Global Studies at Stony Brook University, New York, and also a friend, said: “He was not a nuclear physicist. He was just a physicist. I believe the Iranian [official] media highlight this word ‘nuclear’ to imply he was killed by the Israelis or Americans.”

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