Russian special officer of Russia's Main Intelligence Directorate (GRU) of the Russian General Staff Evgeniy Erofeyev, who was captured in Donbas in 2015 and returned in a prisoner swap for Ukrainian pilot Nadia Savchenko in 2016, was killed shortly after he returned to Russia, according to Russian serviceman Viktor Ageyev, who is under arrest in Donbas.

"Have you heard what happened to GRU Erofeyev after he returned? They took him out. They killed him. I know this for a fact. Everyone is talking about this, here, there, on that side. Everyone knows they took him out. Because he said too much," Ageyev said in an interview with Russia's Novaya Gazeta newspaper published on Sunday.

Asked whether the incident was raised in order to scare him, Ageyev responded, "No. They wouldn't have started to talk about it. I am sure, although I am not sure of anything. I just want them to get me out of here."

As earlier reported, Russian serviceman Evgeniy Erofeyev and Aleksandr Aleksandrov were captured by Ukrainian soldier on May 16, 2015 near Schastia in Luhansk region while attempting to seize a strategic bridge after a skirmish with Ukrainian soldiers. As a result of the fighting, one Ukrainian soldier died.

Ukrainian soldiers on June 24, 2017 near Zholobok in Slavianoserbsky district, Luhansk region battled a militant reconnaissance group. They took four militants prisoner, including Ageyev, who is a contract soldier in the Russian armed forces.

Head of Ukraine's SBU Security Service Vasyl Hrytsak has said Ageyev's activities in Ukraine qualify as terrorism.

According to media reports, Ageyev's mother has travelled to Ukraine to meet with her son.