Microsoft confirmed today that it is the latest US victim to receive an anthrax-infected letter, believed to have been sent by terrorists.

The Redmond Giant said that a letter sent from Malaysia to the Reno, Nevada offices of its licensing branch last week has tested positive for anthrax spores.

Out of three tests, completed this weekend, two showed positive for traces of the potentially deadly disease.

"We are taking this situation very seriously," a Microsoft representative told vnunet.com.

"Obviously, our first concern is for the health and safety of the public and our employees. We are working closely with law enforcement and health officials to ensure the safety of the general public," the company added.

The infected material will be sent to the US Centre for Disease Control (CDC) for analysis, while Microsoft employees are being questioned to find out who may have handled the letter.

It is not known at what point in the mail delivery chain the infected material found its way into the envelope.