Authorities in Novosibirsk say suspects accused of painting the colors of the Ukrainian flag on a monument to Lenin in the Russian city have been detained.
Activists sprayed yellow and blue paint on a Lenin monument, as well as a Soviet tank and an artillery piece at a World War Two memorial, in the Siberian city last week.
They painted the word "Glory to Ukraine!" on the Lenin monument.
Police opened an investigation on a charge of "vandalism motivated by political, ideological, racial, ethnic or religious hatred."
Regional governor Vladimir Gorodetsky said on December 15 that suspects had been detained, but not say how many or give their names.
Russia annexed Crimea from Ukraine in March and has supported pro-Russian rebels whose conflict with government forces has killed more than 4,600 people in eastern Ukraine since April.