( CNN) Parts of an operation linked to Russian military intelligence targeting the US Senate and conservative think tanks that advocated for tougher policies against Russia were frustrated last week, Microsoft announced early Tuesday.

In its proclamation, Microsoft said it executed a court order giving it control of six websites created by a group known as Fancy Bear. The group was behind the 2016 hacker of the Democratic National Committee and directed by the GRU, the Russian military intelligence unit, according to cybersecurity firms.

The websites could have been used to launch cyberattacks on candidates and other political groups ahead of November's elections, the company said.

Microsoft stops Kremlin-based hackers

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