Muhammad el-Baradei, head of the International Atomic Energy Agency (IAEA), made his remarks today in Moscow after IAEA inspectors visited the site, where Washington has accused Iran of working on secret atomic weapons.
El-Baradei said Iran told the IAEA that the site, recently cleared of buildings and topsoil, had been a military-research center.
"That site now is dismantled," el-Baradei said. "The Iranian authorities stated that this was a physics institute that later on turned to be a biotechnology-research and -development center."
El-Baradei said inspectors had taken environmental samples from the site for testing for nuclear materials. He praised Iran for giving prompt access to inspectors.
El-Baradei also said a nuclear monitoring device found at the site might have been made in the United States, which has called on countries not to export to Iran machinery that could be used in arms production.
[For a related story on el-Baradei's visit to Russia, click here