MOSCOW (AP) — Russian investigators have charged two associates of opposition leader Alexei Navalny with fraud and pushed for the search for another one.

The Investigative Committee, which normally deals with high-profile crimes, said on Wednesday that Nikolai Lyaskin and Konstantin Yankauskas have been charged with fraud linked to their work on Navalny’s mayoral campaign last summer. Yankauskas was put under house arrest while Lyaskin was asked not to leave the city.

The investigators also said they were seeking an arrest warrant for Navalny’s right hand, Vladimir Ashurkov.

Navalny has been under house arrest since February for charges in the second criminal case against him.

The charges seem to be putting further pressure on Russia’s embattled opposition. The three men were running for seats at Moscow’s city legislature later this year.

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