Oleh Sentsov in a Russian penal colony / Photo from facebook.com/denisovaombudsman

Illegally convicted Ukrainian film director Oleh Sentsov, who has been on hunger strike in a Russian penal colony since May 14, 2018, has lost weight and is 72 kg now.

"He is taking things on the chin, not going to give up and asks us not to give up in any way. He has lost weight to 72 kg," Ukrainian activist, member of NGO AutoMaidan Oleksiy Hrytsenko said on Facebook on September 4, citing a letter he has got from Sentsov.

"He asks to write and tell [him] about what has been happening, as he gets information from letters only," Hrytsenko added.

Read alsoEU again calls on Russia to free Sentsov

As UNIAN reported earlier, Sentsov was arrested in Russian-occupied Crimea in spring 2014 and in August 2015 he was sentenced to 20 years in prison following an unfair trial where he faced "terrorism" charges stemming from his opposition to Russia's occupation of Crimea.

He has been serving his term in a penal colony in the town of Labytnangi, Russia's Yamal.

He went on hunger strike on May 14, demanding that Russia free all Ukrainian political prisoners.

Sentsov's cousin, Moscow-based journalist Natalya Kaplan says his condition is critical and things are "catastrophically bad."