VIENNA, Austria, 23 June 2003 — Experts from the UN atomic agency have accounted for tons of natural and low-enriched uranium feared looted from Iraq’s largest nuclear research facility, diplomats said Friday.

The diplomats, who are familiar with the workings of the International Atomic Energy Agency, agreed to talk on the success of the mission to secure the uranium at the Tuwaitha facility only on condition of anonymity.

The mission was restricted by the US-led interim administration of Iraq and experts were not allowed to examine Iraqis reportedly sickened by contact with materials stolen from the Tuwaitha center, 20 kilometers (12 miles) south of Baghdad, said the diplomats.

They also said that the IAEA team was unable to determine whether hundreds of radiological sources used in research and medicine across the country were secure or if they constituted a danger to the population. The materials at these sources could potentially be used to make dirty bombs by terrorists using them with conventional explosives.

After-office-hours calls to IAEA spokespeople for comment went unanswered.

The experts, who began their work at the Tuwaitha research facility June 7, were not able to determine how much damage was done to the plant during the war.

Tuwaitha, Iraq’s largest nuclear facility and now defunct, was left unguarded for two weeks after Iraqi troops fled the area on the eve of the war.

US troops did not secure the area until April 7. In the meantime, looters from the surrounding villages stripped it of uranium storage barrels they later used to hold drinking water. Villagers said the looting continued when the Marines handed over control to another unit in mid-April.

Tuwaitha was thought to contain hundreds of tons of natural uranium and nearly two tons of low-enriched uranium, which could be further processed for arms use.

The diplomats did not detail how much uranium had been looted and where it was found, but it appeared much of it was on or near the site.

US military officials who accompanied the IAEA team said last week that initial assessments indicated most of the uranium that had been stored at the Tuwaitha Nuclear Research Center was accounted for.

Although at least 20 percent of the containers which stored the uranium were taken from the site, it appeared that looters had dumped the uranium before taking the barrels.

US military experts involved in the cleanup of the nuclear site found piles of uranium in the storerooms and had also purchased most of the looted barrels back from the surrounding villages at the cost of $3 per barrel.

The uranium was stored in plastic bags placed inside plastic blue barrels. Nuclear experts with the US military said from their assessments, looters apparently tossed the bags, some of which opened, onto the ground and took the empty barrels home.

Villagers said they then used the barrels for storage. Some reported feeling unwell afterward but symptoms such as exhaustion and skin irritations went away after several weeks.

The military officials said they haven’t detected any signs of ill health effects. Still, Iraqi health officials are conducting a survey in villages around the site.

The arrival of the UN group — seven men, none of them American, whose expertise ranges from nuclear physics to arms-control analysis — marked the first time since before the war began that representatives from the agency returned to Iraq.

The IAEA has long monitored Iraq’s nuclear programs and has questioned US claims that Saddam Hussein was reviving his nuclear weapons program.

The Bush administration cut off the IAEA from the weapons hunt after its assessments of Iraq’s nuclear programs hurt Washington’s efforts to win international backing for the war. Relations further soured amid early war reports that US troops had failed to secure Tuwaitha and other nuclear facilities in Iraq from looters.

After weeks of international pressure and urging from the IAEA, the Pentagon finally agreed to let a small team in under strict guidelines that permitted the experts to visit Tuwaitha on a one-time-only trip that must be wrapped up by June 25.