Iran's foreign ministry has said there are signs that Israel and the United States were behind the killing of a nuclear physics professor who died in a bomb attack in the capital Tehran on Tuesday.

State broadcaster IRIB reported on its website that Masoud Ali-Mohammadi, who worked as a lecturer at Tehran University, died when a remote-controlled bomb exploded near his home.

Iranian media also said the scientist was a supporter of Iran's regime and was killed by 'anti revolutionary' groups.

Radio Netherlands Worldwide’s Tehran correspondent Thomas Erdbrink says, however, there may be evidence that Mr Ali-Mohammadi was in fact a supporter of the opposition.

“He was apparently a supporter of Mir Hossein Mousavi. A list has emerged with his name on it, signing a letter of support for this opposition leader… [however] it’s completely unclear why this man has been murdered at this point.”

Such attacks are extremely rare in the Iranian capital, and this one comes at a time of heightened tension with the West over Iran’s nuclear programme. Western leaders suspect Iran may be developing its own nuclear weapons project. Tehran denies this and says it is only seeking to generate nuclear energy.

It is still unclear whether Mr Ali-Mohammadi was actively involved in the country’s nuclear programme. An internet search reveals that a scientist of that name has co-written research papers on ‘dark energy’, a highly theoretical area of cosmology.

Opposition supporters, who have faced increased suppression since last year’s post election protests, fear the bombing may provide an opportunity for further clampdowns by the Iranian authorities.

Listen to the Newsline interview with Thomas Erdbrink in Tehran

Sources: RNW, Reuters.