President of the American Association for Research in Baghdad McGuire Gibson, right, gestures as  Director of the British Museum Neil MacGregor  looks on during a news conference held at the  Paris-based U.N. Educational, Scientific and  Cultural Organization, Thursday April 17, 2003.  Some 30 experts met at the UNESCO head- quarters Thursday to attempt to draw an inventory  of recent cultural destruction in Iraq and to  catalogue the missing artifacts. UNESCO Director- General Koichiro Matsuura, unseen, urged the  United Nations to impose a temporary embargo  on Iraqi cultural objects. (AP Photo/Michel Euler)

PARIS - Professional thieves, likely organized outside Iraq, pillaged the nation's priceless ancient history collections by using the cover of widespread looting - and vault keys - to make off with irreplaceable items, art experts and historians said Thursday.  The bandits were so efficient at emptying Iraqi libraries and museums that reports have already surfaced of artifacts appearing on the black market, some experts said. Certain thieves apparently knew exactly what they wanted from the irreplaceable Babylonian, Sumerian and Assyrian collections, and exactly where to find them.  "It looks as if part of the theft was a very, very deliberate, planned action," said McGuire Gibson, president of the American Association for Research in Baghdad. "It really looks like a very professional job."  Gibson was among 30 art experts and cultural historians assembled by the U.N. Educational, Scientific and Cultural Organization to assess the damage to Iraq's heritage in the aftermath of the U.S.-led invasion.

In Washington, the FBI announced Thursday it had sent agents to Iraq to assist in recovering stolen antiquities. 

"We are firmly committed to doing whatever we can to secure these treasures to the people of Iraq," FBI Director Robert Mueller told a news conference at the Justice Department. 

But it remained unclear exactly what was gone and what survived the looting and thievery. With many museum records now in ashes and access to Iraq still cut off, it could take weeks or months to answer those questions. 

Establishing a database was a key to finding out what had survived, and tracking down what was stolen, the experts said. 

Neil MacGregor, director of the British Museum, said some of the greatest treasures - including gold jewelry of the Assyrian queens - were placed in the vaults of the national bank after the 1991 Gulf War. There was no information on whether those items remained inside. 

The National Museum, one of the Middle East's most important archaeological repositories, was ransacked. But it was unknown whether one of its greatest treasures, tablets containing Hammurabi's Code, one of the earliest codes of law, were there when the looting began. 

The pillaging has ravaged the irreplaceable Babylonian, Sumerian and Assyrian collections that chronicled ancient civilization in Mesopotamia - the home of modern-day Iraq. Although much of the looting was haphazard, experts said some of it was highly organized. 

"They were able to obtain keys from somewhere for the vaults and were able to take out the very important, the very best material," Gibson said. "I have a suspicion it was organized outside the country. In fact, I'm pretty sure it was." 

Many at the meeting feared the stolen artifacts have been absorbed into highly organized trafficking rings that ferry the goods through a series of middlemen to collectors in Europe, the United States and Japan. 

The FBI was cooperating with the international law enforcement organization Interpol in issuing alerts to all member nations to try to track any sales of the artifacts "on both the open and black markets," Muller said. 

Ahead of the war, Iraq's antiquities' authorities gathered artifacts from around the country and moved them to Baghdad's National Museum, assuming the museum would not be bombed, Gibson said. 

"They did not count on the museum being looted," he said. 

The network of antiquities dealing in Iraq is well-developed, escalating far beyond the ability of authorities to stop it following the 1991 Gulf War. Thousands of antiquities had disappeared from the country even before the current war. 

The trafficking feeds off of Iraq's poverty-stricken people, said Salma El Radi, an Iraqi archaeologist. "If you need to feed your family and the only way to do it is by looting a site, you're going to loot a site," El Radi said. 

Much anger has been directed at U.S. troops, who stood by and watched as Iraq's treasures were carted off. 

Koichiro Matsuura, director-general of Paris-based UNESCO, called Thursday for a U.N. resolution imposing a temporary embargo on trade in Iraqi antiquities. Such a resolution would also call for the return of such items to Iraq, he said. 

"To preserve the Iraqi cultural heritage is, in a word, to enable Iraq to successfully make its transition to a new, free and prosperous society," the UNESCO chief said.