BAGHDAD, Iraq -- When the top U.N. arms experts were in town, Demetrius Perricos put on a suit and a tie and slipped into anonymity, lurking quietly in the background as his bosses took center stage. But appearances can be deceiving.
Chief weapons inspectors Hans Blix and Mohamed ElBaradei, who were in Baghdad Sunday and Monday, may often have their pictures splashed across newspapers the world over.
But it's Perricos, a Greek citizen, who is the key figure in the painstaking search for Iraq's alleged banned weapons, a complex undertaking that could spell the difference between war and peace.
A physicist who worked for years for the International Atomic Energy Agency, Perricos set the tone for the current inspections, which resumed in November after a four-year interruption.
On one of the first inspections, Perricos led a convoy of U.N. vehicles in a high-speed drive through twisting and narrow country roads to disguise his ultimate destination - an abandoned biological weapons plant.
Last week, Perricos infuriated the Iraqis again, leading a team of inspectors into two office complexes inside the compound of Iraq's main presidential palace in Baghdad. The next day, he led a search of the Baghdad homes of two Iraqi scientists in the first such inspections.
"Whenever something happens that they don't like very much, they start to complain," he told reporters last week. "But we don't give much attention to their complaints."
A physicist in his mid-60s, Perricos is the director of planning and operations at the U.N. Monitoring and Verification Commission, which handles inspections for chemical and biological weapons. He is often at pains to dismiss any suggestion that his job has anything to do with the politics of the latest U.S.-Iraqi standoff.
"We think of our immediate bosses as political people doing a political job," he said on Nov. 28. "It is not us who are providing an input for war and peace. The judgments are all coming up at the political level, and therefore I sleep very well," he added with a smile.
According to the Athens daily Eleftherotypia, Perricos is the son of a Greek Air Force officer executed by Nazi troops during Germany's occupation of Greece during World War II. He was 8 when his father, Costas Perricos, died.
"Work so that all wars are stopped, people prosper, the countries of Europe unite, and the world is in peace and happiness," Costas Perricos wrote to his family in his last letter from prison, according to Eleftherotypia.
His father's peace message to the message seems to have survived the passage of time.
"We all hope no one goes to war," Perricos told Greece's private Antenna television on Sunday. "As long as the inspections can continue, then we can all hope things will get better.
"You are talking to a man who believes in the inspection process ... world politics do not depend on the inspectors," he told the Greek daily Ta Nea earlier this month.
Perricos, who declined to be interviewed for The Associated Press, told an Antenna reporter before he left Baghdad for Athens Monday that he intended to briefly see his grandchildren at home before continuing to Vienna.
Silver-haired and mustachioed, Perricos is hardly a typical grandfather.
In a sweater, a fleece, a backpack and a pair of rose color shades, he led U.N. teams on at least four inspections last week: the presidential palace compound, the two scientists' homes, a private farm and mobile food labs at the Trade Ministry. Some of these inspections lasted for up to seven hours and on one, the visit to the scientists' homes, he was seen by reporters in heated exchanges with the liaison officers appointed by the government to escort the inspectors.
Perricos first came to Iraq in 1991 as part of the former inspections regime, which folded in 1998 when Iraq decided to stop cooperation with the inspectors, who left the country just before four days of U.S. and British attacks. He left Iraq in 1993 to join the International Atomic Energy Agency inspection team in North Korea.
"I have said many times before - the most important item in an inspection is the inspectors' own sight," he said last week, explaining his professional philosophy. "They have to go in, see and verify then they start to use instruments and everything else to amplify their verification."
Example: a bird may appear to behave and move like a duck, he said, "but at the end it may not be a duck, it may be a swan."