Investigators from the International Atomic Energy Agency have used radiation detection devices during a visit to a looted storage facility at Iraq's main nuclear research facility. Local residents are afraid the looting may have caused widespread radioactive contamination in the area.

Wearing full protection suits, the team of U.N. nuclear experts returned to the al-Tuwaitha nuclear research center trying to determine how much low-enriched uranium may have been looted from the facility and whether any contamination occurred.

Five hundred tons of natural uranium and almost two tons of low-enriched uranium known as yellowcake were stored at al-Tuwaitha.

Following the fall of Iraqi president Saddam Hussein, hundreds of looters ransacked the sprawling facility, emptied some barrels that may have contained radioactive material and then sold the barrels to local residents for two dollars.

In an effort to retrieve the barrels, coalition forces offered to buy them back for three dollars. So far, 100 drums have been recovered. A military official was quoted as saying as much as 20 percent of the uranium stored at the site may be missing.

Local residents are afraid there has been widespread contamination. Some people reportedly washed clothes in the barrels and washed the barrels in the Tigris river.

Some residents living near the facility say they are afraid to drink the local water or eat food produced in the area and, instead, are driving to Baghdad to buy their groceries.

The team of U.N. nuclear experts arrived Friday in Baghdad. They are expected to remain for at least two weeks, and their mission is strictly confined to the al-Tuwaitha facility. They will not be searching for weapons of mass destruction.

That job will go to a team of about 1,400 investigators, mostly from the United States. Those investigators are expected to begin their work sometime this week.