Photo from Yamalo-Nenetsky Area penitentiary authority

Ukrainian filmmaker Oleh Sentsov, who ended his nearly five-month hunger strike in a Russian prison earlier this month, may not survive because of damage to his health, his cousin says.

"Almost all his organs are severely affected," including liver, heart, and brain, Natalya Kaplan told journalists in Kyiv on October 16, as reported by Radio Liberty.

"The end of the hunger strike is a serious procedure, no one can say now whether Oleh will survive," she added.

Russian authorities have not commented publicly on Kaplan's statement.

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Sentsov, a Crimean native who opposed Russia's 2014 takeover of the Ukrainian peninsula, is serving a 20-year prison term in Russia's far northern Yamalo-Nenets region.

He was convicted of terrorism in a trial that he, human rights groups, and Western governments contend was politically motivated.

The filmmaker started a hunger strike on May 14, demanding that Russia release 64 Ukrainians whom he considers political prisoners in Russia.

He ended his protest action on October 6, saying he had to do so to avoid being force-fed by the prison authorities.

At the end of his hunger strike, during which he was kept alive with nutrients administered via a drip, Sentsov had lost 20 kilograms.

Kaplan said her cousin was being treated in an intensive-care unit in the Yamalo-Nenets region.

"Unfortunately, his recent letters are quite pessimistic. He wrote a testament in which he asks not to abandon his children," she also said.

Sentsov has said he was against being transferred to an intensive-care unit.