International weapons monitors are inspecting an idle airfield north of Baghdad, searching for devices that can spray deadly microbes from the air.
UN inspectors in the 1990s learned the Iraqis had successfully tested the Zubaidy device, using it to disperse toxic bacteria from a helicopter, apparently from the airfield at Khan Bani Sa'ad, 20 miles north-east of Baghdad.
More than a dozen helicopters, stripped of their motors, sat on the tarmac as UN inspectors checked the grounds watched by journalists observed from beyond a distant fence.
The inspectors, who also are hunting for signs of chemical and biological agents, seemed interested in holding tanks that could have been used for aviation fuel.
The UN teams said nothing publicly about the day's mission.
It is the fourth day of renewed inspections, after a four-year break, under a UN Security Council mandate for Iraq to finally give up any remaining weapons of mass destruction or face "serious consequences".
Meanwhile, Western warplanes killed four people in a strike on a southern Iraqi oil plant.
Residents of the southern port city of Basra told Reuters by telephone the planes, patrolling a southern "no-fly" zone, hit an oil facility in the city at around noon. They said four people died and several others were wounded.
US Central Command in Tampa, Florida, said it had no information on the report. "We have nothing on it.
US and British warplanes police two no-fly zones in southern and northern Iraq.
PA & AFP