By AJ Vicens

July 31 (Reuters) - One of the Russian government's

premier cyber espionage units is deploying malware against

embassies and diplomatic organizations in Moscow by leveraging

local internet service providers, Microsoft ( MSFT ) said on

Thursday.

The analysis confirms for the first time that Russia's

Federal Security Service, also known as the FSB, is conducting

cyber espionage at the ISP level, according to findings from

Microsoft Threat Intelligence.

"Microsoft ( MSFT ) is now certain that this activity is happening

within Russian borders," Microsoft's ( MSFT ) director of Threat

Intelligence Strategy, Sherrod DeGrippo, told Reuters.

Microsoft's ( MSFT ) findings come amid increasing pressure from

Washington for Moscow to agree to a ceasefire in its war in

Ukraine and pledges from NATO countries to increase defense

spending surrounding their own concerns about Russia.

The analysis tracks an FSB cyber espionage campaign that in

February targeted unnamed foreign embassies in Moscow. The FSB

activity facilitates the installation of custom backdoors on

targeted computers, which can be used to install additional

malware as well as steal data.

Reuters could not determine which embassies were targeted.

The U.S. State Department did not respond to a request for

comment.

Russian diplomats did not immediately respond to a request

for comment. Moscow routinely denies carrying out cyber

espionage operations.

The hacking unit linked to the activity, which Microsoft ( MSFT ) tracks

as "Secret Blizzard" and others categorize as "Turla," has been

hacking governments, journalists and others for nearly 20 years,

the U.S. government said in May 2023 after the FBI disrupted one

of its long-running operations.