UNITED NATIONS (AP) - The U.N. nuclear chief warned Friday that the threat of nuclear terrorism has not diminished, saying a key risk is that terrorists could detonate a so-called "dirty bomb" to contaminate a major city.
Yukio Amano, director general of the International Atomic Energy Agency, told a high-level meeting on the sidelines of the U.N. General Assembly that a dirty bomb - using conventional explosives and some nuclear or radioactive material - wouldn't be a full-fledged nuclear bomb but it could lead to mass panic and serious economic disruption.
"We must therefore maintain the utmost vigilance in protecting nuclear and other radioactive material and nuclear facilities," he said.
Amano said more than 2,200 incidents have been registered on the International Atomic Energy Agency's "Illicit Trafficking Database" since it was established in 1995.
"Most of these are fairly minor, but some are more serious," he said. "Taken together, they show that much work is needed and that we must never become complacent."
Amano said urgent action is needed to ratify an amendment to the U.N. Convention on the Physical Protection of Nuclear Materials which was adopted in 2005 but hasn't entered into force.
The treaty covers only the physical protection of nuclear material in international transport. The amendment would expand its coverage to include the protection of nuclear material in domestic use, in storage and transport, and the protection of nuclear facilities against acts of sabotage.
Iran's Foreign Minister Ali Akbar Salehi, addressing the meeting as chair of the Nonaligned Movement which comprises 120 mainly developing countries, alluded to Israeli threats to attack Iranian nuclear facilities if it determines Iran is close to producing a nuclear bomb. Iran insists its nuclear program is peaceful and aimed at producing nuclear power.
He said the movement, known as NAM, "reaffirms the inviolability of peaceful nuclear activities and that any attack or threat of attack against peaceful nuclear facilities - operational or under construction - constitutes a grave violation of international law, principles and purposes of the U.N. Charter and regulations of the IAEA."
Salehi said NAM recognizes "the urgent need" for a new international legal instrument "prohibiting attacks or threat of attacks on nuclear facilities devoted to peaceful uses of nuclear energy."
Secretary-General Ban Ki-moon, who called the meeting, said "the prospect of terrorists acquiring nuclear materials is one of the most unnerving threats imaginable."
"Yet some have already stated their hopes of obtaining nuclear weapons," he said. "Still others may be working in the shadows to achieve this goal."
Ban told the ministers and diplomats that "we must use all our tools to contain this nuclear genie."
U.S. Deputy Secretary of State William Burns said obtaining nuclear weapons "is a longstanding goal for a weakened but still dangerous al-Qaida."
The 400 incidents reported to the IAEA since 1995 involving smuggling of nuclear or radioactive material "suggest that the risk to all of us is very real, and complacency is a luxury we cannot afford," he said.
Burns said the United States is working with many countries to remove and eliminate vulnerable nuclear material including upgrading security at nuclear facilities around the world and converting nuclear research reactors that use high-enriched uranium to low-enriched uranium.
The United States also is encouraging the development of national teams to counter nuclear smuggling and working with countries to secure international land borders, seaports and airports and improve their efforts to detect and respond to smuggling activities, he said.
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