The mother of Russian opposition leader Alexei Navalny has demanded that President Vladimir Putin return her son’s body after his recent imprisonment and alleged poisoning.

Yulia Navalnaya made a public plea, accusing Putin of being responsible for her son’s deteriorating health and calling for his immediate release.

Navalny, a fierce critic of the Russian government, was arrested in January upon returning from Germany, where he had been receiving medical treatment after being poisoned with a nerve agent last year.

His mother’s emotional plea has sparked outrage and calls for justice from both domestic and international human rights organizations.

The Kremlin has denied any involvement in Navalny’s poisoning and imprisonment, but pressure continues to mount on Putin to address the situation and release the opposition leader.