Photo courtesy of Alexander Demidenko

The Russian activist Alexander Demidenko, who helped Ukrainian refugees in the Belgorod region to return home from Russia, was revealed to have committed suicide while in pretrial detention on Friday, local news website Bel.ru reported on Tuesday, citing the Belgorod Federal Penitentiary Service (FSIN).

The FSIN said it was now conducting an investigation into the death in tandem with Russia’s Investigative Committee.

Demidenko’s son Oleg announced his father’s death on Monday, and though he said he had no details, he added that he believed his father may have committed suicide.

In October, Demidenko disappeared while accompanying an elderly woman with cancer to the Kolotilovka border crossing between Russia and Ukraine, BBC News Russian reported. It subsequently transpired that he had been detained by security forces.

Alexander Demidenko. Photo: “We can explain”

He was initially remanded in custody for 10 days and his home was searched. He was then charged with illegal arms trafficking when security forces said they had found a grenade and two detonators at his home. He had been in pretrial detention ever since.

Before his arrest, Demidenko provided assistance to Ukrainians in Russia’s southwestern Belgorod region who wanted to leave the country via the only remaining open border checkpoint between the two countries. He also regularly hosted refugees who had been displaced from the Russian-occupied regions of Ukraine and helped them return home.