Iran scientist death adds to growing stack of nuclear stresses The tension between Iran and the West has cost the life of another nuclear scientist in Tehran. A limpet bomb on his car killed 32-year-old Mostafa Ahmadi Roshan on Wednesday. He worked at the Natanz uranium enrichment plant. The chemical engineer's driver also died, Iranian media said, and a passer-by was slightly hurt. In a twelve-month period, three other scientists, two in the nuclear programme, have been murdered in the same way in Iran - five over two years. Media there have called for reprisals against Israel, believing that country is responsible for the attacks. Iranian analyst Hassan Hanizadeh shared that belief. Hanizadeh said: "Through these acts of terror, Israel will try to prevent the nuclear activities of Iran. The Islamic Republic has evidence - which it will hand over to the United Nations - which shows that Israel has tried to create security issues in Iran by terror and instigating fear. Western countries are more convinced than ever that Iran is pursuing a nuclear bomb. Analysts saw the latest assassination less as a reaction to recent events than part of a longer-running, covert prevention effort. However, a few days ago, the UN's Atomic Energy Agency said Iran had begun producing 20 percent enriched uranium at Fordow, near Qom, in a deep bunker. This is a higher grade than is needed for civil uses. Analyst Carne Ross, with non-profit organisation Independent Diplomat, tied in other factors: Ross said: "The Iranian naval exercise in the Strait of Hormuz, the US counter threat that it must keep the strait open after Iranian threats they might close the strait. There has also been the downing of an American drone, allegedly in Iranian airspace. We are seeing an increase in the rhetoric, too, between the US, and indeed the West, and Iran. Against a backdrop of Iranian naval activity, the US military said on Wednesday that a new aircraft carrier strike group had arrived in the Arabian Sea and that another was on its way to the region, but denied any link to recent tensions with Iran. The Pentagon has said all types of its ships routinely pass into the Persian Gulf - also known as the Arabian Gulf. More about: Death, Diplomatic tension, Iran, Nuclear research, Tehran