The Russian government used a popular antivirus software to secretly scan computers around the world for classified U.S. government documents and top-secret information, modifying the program to turn it into an espionage tool, according to current and former U.S. officials with knowledge of the matter, WSJ reports.

The software, made by the Moscow-based company Kaspersky Lab, routinely scans files of computers on which it is installed looking for viruses and other malicious software.

Read alsoRussia steals U.S. cyber capabilities via antivirus software - mediaBut in an adjustment to its normal operations that the officials say could only have been made with the company’s knowledge, the program searched for terms as broad as “top secret,” which may be written on classified government documents, as well as the classified code names of U.S. government programs.

As UNIAN reported earlier with reference to RFE/RL, the U.S. Homeland Security on September 13 ordered all U.S. federal agencies to phase out use of Kaspersky Lab software products, citing “ties between certain Kaspersky officials and Russian intelligence and other government agencies.”

A statement said executive-branch departments and agencies have up to 90 days to begin discontinuing use of Kaspersky software and remove the products from computer systems.