(AFP) Prime Minister Dr Mahathir Mohamad today urged the United States to provide details about a letter containing anthrax allegedly sent from here to a Microsoft office in the US.

"Once we get information, we will investigate. At this moment we don't know anything.

"We have no information. They don't give us any information," he told reporters.

On Sunday, the government pledged full cooperation with the United States in investigating the case.

US reports said a letter containing a cheque, which had been sent by Microsoft to one of its vendors here, was returned to the Microsoft office in Carson City, Nevada, containing pornographic pictures.

It was tested and found positive for traces of anthrax, which has become a focus of bioterrorism fears in the US since several people were found to have been exposed to the rare disease recently. One of them died.