Photo by Anton Naumliuk

On August 25, Moscow police detained on Red Square a Russian activist Anna Krasovitskaya who stood there with a poster in support of a Kremlin's political prisoner, Ukrainian filmmaker Oleh Sentsov.

Krasovitskaya is the granddaughter of Natalia Gorbanevskaya, one of the participants in the "Demonstration of the Seven" in August 1968, RFE/RL reports.

Back in 1968, a group of human rights activists took to Red Square, protesting against the invasion of Czechoslovakia by Soviet troops and the suppression of the "Prague Spring."

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UNIAN memo. The FSB detained Sentsov in the occupied Crimea in the spring of 2014. He was later transferred to Russia.

In August 2015, Sentsov was sentenced to 20 years in prison on fabricated charges of organizing terrorist attacks and setting fire to Russian party offices.

He is being kept in a distant Russian colony "Polar Bear" in Labytnangi, Yamal.

On May 14, Sentsov went on a hunger strike demanding the release of all Ukrainian political prisoners. The film director's condition is deteriorating rapidly, while prison administration assures that his state of health is assessed as satisfactory.

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On July 13, it became known that the mother of film director, Lyudmila Sentsova, wrote a letter to Russian President Vladimir Putin requesting pardon for her son. The Kremlin responded that the pardon procedure must start with the convict's personal petition.

Political figures and activists in Ukraine and worldwide continue to demand that Russia release the illegally detained Ukrainians.

The rallies are held under the slogans #FreeOlegSentsov and #SaveOlegSentsov.