Supporters of Crimean film director Oleg Sentsov have held a rally in Ukrainian capital, Kyiv, to mark two years since his conviction in Russia following a trial that has drawn international condemnation.

The Kyiv-based Solidarity Committee organized a picket in front of the Russian Embassy in Kyiv on August 25 to express support for Sentsov and his co-defendant, Oleksandr Kolchenko.

Over a dozen activists held placards saying, “Those in freedom, let us help political prisoners” and “For your freedom and ours.”

The demonstrators also urged passersby to send their letters of support to Sentsov and Kolchenko by mail.

Activists planned another rally in the southwestern city of Odesa on August 25 to call for the release of inmates who are “victims of the Kremlin’s anti-Ukrainian campaign and are in Russia’s prisons on fabricated charges.”

“Come, your participation is important because at least 46 citizens of Ukraine remain hostages of the Russians!” the organizers said on Facebook.

A Russian court convicted Sentsov and Kolchenko on August 25, 2015, of conspiring to commit terrorism in the Crimea region, which Russia seized in March 2014 after sending in troops and staging a referendum denounced by 100 countries as illegitimate.

They were sentenced to 20 years and 10 years in prison, respectively.

Both have consistently denied the accusations, with Sentsov, who has opposed Russia’s takeover of Crimea, saying that a “trial by occupiers cannot be fair by definition.”

The trial of Sentsov and Kolchenko was described by international rights groups as politically motivated and politicians, officials, film directors, and other artists have called for their release.

PEN America announced in March that it will honor Sentsov with its 2017 PEN/Barbey Freedom to Write Award, saying the charges against him “have been condemned by human rights groups as fabrications by a Russian government intent on silencing dissent.”

It said Sentsov is widely regarded for work that includes two short films — A Perfect Day For Bananafish and The Horn Of A Bull — and a full-length feature film, Gamer, that debuted to acclaim at the 2012 International Film Festival in Rotterdam.

His writings include scripts, plays, and essays, and he has continued to produce prolifically from prison, a statement said.

Rights activists say Russia has jailed a number of Ukrainians on trumped-up, politically motivated charges since Moscow seized control of Crimea in 2014.

In March, the European Parliament called on Russia to free more than 30 Ukrainian citizens who were in prison or other conditions of restricted freedom in Russia, Crimea, and parts of eastern Ukraine that are controlled by Russia-backed separatists.