Russian police have searched the Moscow homes of at least two employees of the Library of Ukrainian Literature.
The lawyer for the library's director said police searched the homes of Anna Pavlenko and Tatiana Muntian early on December 14.
The Russian Investigative Committee said searches were also made in other apartments belonging to individuals who "did not work for the library, but were receiving salaries from it."
The library's director, Natalya Sharina, 58, was detained in late October and charged with inciting extremism and ethnic hatred.
She is being held under house arrest.
Russia's Investigative Committee said authorities had found books in Sharina's library by Ukrainian ultranationalist author Dmytro Korchynsky, whose works are banned in Russia.
Sharina rejected the charges, saying the books had been planted in her library by police.
Based on reporting by Interfax and TASS