A little-known Syrian opposition group has said it is ready to exchange the bodies of five Russian crew, whose helicopter was downed in north-western Syria this week, for prisoners held in government jails.
The self-styled Public Institution for Prisoners group posted online what appears to be the identity cards of the five.
"We in the Public Institution for Prisoners are the only body authorized to negotiate with the Russian side regarding the bodies of the crew of the Russian military plane that fell in northern Syria," the group said in a Facebook statement in Arabic released late Thursday.
The group has describes itself as an independent organization interested in prisoners' affairs.
It also demanded an end to the Syrian government's siege on rebel-held areas in Syria.
The group did not say how many prisoners it wants to be released.
On Monday, Russia's presidential spokesman confirmed that a Russian Mi-8 helicopter had been shot down in Syria's north-western Idlib province.
The Russian defence Ministry said the helicopter was carrying five people when it was downed by fire from the ground.
It added that the helicopter was returning to the Khmeimim air base on Syria's north-western coast after delivering humanitarian aid to the northern city of Aleppo.
In September 2015, Russia started an air campaign in war-torn Syria in support of President Bashar al-Assad's regime.