Several vials of potentially dangerous chemicals have been found at a United Nations building in New York.
The material, said to include phosgene, is said to have been removed from Iraq during inspections of chemical facilities a decade ago.
The UN said the vials had been found by inspectors as they cleared out an office near the UN’s headquarters.
The material “could be potentially hazardous”, but did not pose any immediate risk, a UN spokeswoman said.
UN deputy spokeswoman Marie Okabe said the substances had been secured by experts at the UN Monitoring, Verification and Inspection Commission (Unmovic).
The office area had been screened, she said, and no toxic vapours were found.
The metal and glass vials, stored in a sealed plastic bag, were discovered in the process of emptying Unmovic’s office building in Manhattan.
“The only information we have of the contents of that bag is from an inventory of a 1996 inspection which indicates that one of the items may contain phosgene, an old generation chemical warfare agent,” Ms Okabe said.
The US authorities have been called in to assist with the safe removal of the material.
Phosgene, a yellow-green gas smelling of swimming pools or newly-mown hay, was widely used during World War I as a choking agent. The Russian military has also claimed that it has been used in Chechnya.
Unmovic’s inspectors were withdrawn from Iraq in March 2003 and in June this year the UN decided to end its mandate.