Many suspects in Iran scientist attack, says ex-Mossad chief

Moments after a mystery motorbike pulled up alongside Mostafa Ahmadi Rishan's car and attached a magnetic bomb to it - the 32 year old chemist and nuclear scientist was dead.

The attack on the streets of the Iranian capital is just the latest in a series of daylight killings of scientists which Iran accuses both Israel and the United States of orchestrating.

Danny Yatom, a former head of the Israeli intelligence service Mossad, said there were many suspects who were capable of carrying out the attack.