WASHINGTON, May 9 —The FBI has sabotaged a suite of malicious software used by elite Russian spies, US authorities said today, providing a glimpse of the digital tug-of-war between two cyber superpowers.

Senior law enforcement officials said FBI technical experts had identified and disabled malware wielded by Russia’s FSB security service against an undisclosed number of American computers, a move they hoped would deal a death blow to one of Russia’s leading cyber spying programs.

“We assess this as being their premier espionage tool,” one of the US officials told journalists ahead of the release. He said Washington hoped the operation would “eradicate it from the virtual battlefield.”

The official identified the FSB hackers behind the malware with a notorious hacking group known as “Turla,” which has been active for two decades against a variety of Nato-aligned targets.

The official spoke to journalists on condition that he not be named.

Russian diplomats did not immediately return a message seeking comment. Moscow routinely denies carrying out cyberespionage operations. — Reuters