AMERICAN forces in Iraq say they have discovered 11 mobile “chemical and biological laboratories” buried in ground near a factory filled with empty artillery shells.

As the political pressure on Washington and London mounts to find concrete evidence of Saddam Hussein’s weapons of mass destruction, particularly after a series of false alarms that a “smoking gun” had been uncovered, American arms experts were last night analysing the 20ft by 20ft “large metal vans” unearthed near Karbala, south of Baghdad.

General Benjamin Freakly, commander of the 101st Airborne Division 2nd Brigade, which made the discovery after fighting near Karbala last week, told CNN yesterday: “(They found 11 buried . . . large metal 20ft by 20ft vans, buried in the ground. They are dual-use chemical labs, biological and chemical labs . . . close to an artillery ammunition plant, which had empty shells.

“It is too early to tell if this is evidence of banned weapons (programmes but clearly it was new equipment, a lot of money in the 2002/2003 time period spent in that camp, probably over $1 million-worth of capability in these 11 vans and we continue to develop (the investigation with better expertise.”

General Freakly added that 1,000lb of documentation was found buried with the mobile laboratories and each “chemical lab” could store 4,467 drums of material. He said no chemical or biological weapons were found with the laboratories.

“Initial reports indicate that this is clearly a case of denial and deception by the Iraqi Government and that these chemical labs were present, and we just have to determine what in fact they were being used for,” he said.

One of the key accusations made against Saddam’s regime by Colin Powell, the US Secretary of State, when he addressed the UN Security Council in February was that Iraq had easily hidden mobile laboratories capable of making weapons-grade chemical and biological material.

As each day passes since the demise of Saddam’s regime, President Bush and Tony Blair are keenly aware that the discovery of a “smoking gun” has become increasingly urgent. The main diplomatic and moral justification for invading Iraq rested on their repeated assertion that Saddam was hiding chemical and biological weapons, and as coalition troops have spread throughout the country the question of why no incriminating evidence has been found has become acute.

General Tommy Franks, the coalition commander, said on Sunday that it could take a year to search every site in Iraq where weapons of mass destruction might be hidden. He said that up to 3,000 locations were earmarked for visits, which are progressing at the rate of five to fifteen a day.

Pressure has also mounted because repeated finds that appeared to show evidence of banned weapons have turned out to be innocent discoveries. Last week, for example, the 101st Airborne believed they had discovered tonnes of nerve agent. Further analysis demonstrated that it was pesticide.

Some of General Powell’s accusations were also disputed yesterday by two former UN weapons inspectors. Joem Siljeholm, a Norwegian, and a German, said that parts of General Powell’s presentation were misleading and completely wrong.

They said that mobile laboratories described by Mr Powell did not exist. They also said that there had been no factories making weapons of mass destruction in a series of photographs produced by General Powell.

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