Fifteen Russian mercenaries deceased due to the blast at an ammunitions depot in Deir-ez-Zor province. Syrian observatory for human rights reported that on Thursday.
A group of the militants escorted government troops as they proceeded to oil and gas depots on the eastern banks of Euphrates river in Deir-ez-Zor. The explosion occurred at a local arms depot, located in the area held by the Syrian democratic forces that enjoy the U.S. support.
The mercenaries apparently attempted to get a hand on the weapons, but they triggered an explosive device instead.
23 men deceased in the blast, inlcuding fifteen Russians and another eight local mercenaries of Bashaar al-Assad.