Prosecutors Wednesday searched the offices of 14 West German companies suspected of helping Libya build a chemical weapons factory, authorities said.

A spokesman for the prosecutor's office in Offenburg, Hubertus Voegele, said one of the firms searched was Imhausen-Chemie in Lahr, which is suspected of playing a major role in building and equipping the Libyan plant.Voegele said the searches were conducted "on suspicion that export laws had been violated." He declined to name the other firms whose offices were searched, but he added they were located throughout the country.

The U.S. government says the plant at Rabta, 60 miles south of the Libyan capital of Tripoli, was built to make poison gas. Libya says it will manufacture medicine.

Bonn officials initially dismissed the U.S. allegations but have now launched a criminal investigation to determine if Imhausen-Chemie and other companies illegally shipped arms, hazardous substances or components that can be used to produce them.

The affair has deeply embarrassed the West German government.

On Tuesday, news reports said an Imhausen-Chemie employee had confirmed allegations the company played a key role in building the Libyan plant.

The weekly Stern magazine said Imhausen-Chemie and a government-owned company were aware that blueprints that were supposed to be shipped to Hong Kong to build a pharmaceuticals plant had ended up in Libya.

The ARD television network late Tuesday reported that Klaus Hess, a technical draftsman with Imhausen-Chemie, "is said to have given evidence that Imhausen shipped parts and chemicals to Libya, and further that Imhausen employees helped build the facility in Rabta."