The head of the IAEA, Mohamed El Baradei, said last November that the ruthlessness of the September 11 attacks had alerted the world to the potential of nuclear terrorism, making it "far more likely" that terrorists could target nuclear facilities, nuclear material, and radioactive sources worldwide. "
The IAEA helps countries around the world prevent, intercept, and respond to terrorist acts and other nuclear safety and security incidents. It has the only international response system in place capable of acting immediately to assist countries in the event of a radiological emergency caused by a nuclear terrorist attack.
Although terrorists have never used a nuclear weapon, reports that some terrorist groups, particularly al-Qaeda, have attempted to acquire nuclear material is a cause of great concern.
According to the IAEA, since 1993 there have been 175 cases of trafficking in nuclear material and 201 cases of trafficking in other radioactive sources (such as for medical and industrial uses). However, only 18 of these cases have actually involved small amounts of highly enriched uranium or plutonium, the material needed to produce a nuclear bomb.
IAEA experts believe the quantities involved are not sufficient to construct a nuclear explosive device. "However, any such materials being in illicit commerce and conceivably accessible to terrorist groups is deeply troubling," said El Baradei.

