According to International Christian Concern (ICC), the Armenian Church leaders were traveling in car to Deir ez-Zor to inspect an Armenian Catholic Church which has suffered damage because of the Syrian conflict.
The organisation said Fr Hanna Bidu, also known as Father Abrahim Petoyan, was killed instantly during when the attackers opened gunfire on the vehicle. His son, Fr Hovsep Petoyan (pictured above), reportedly died at the hospital as a result of the injuries. The deacon, Fati Sano from the Armenian al-Hassakeh Church was wounded.
ISIS's official Amaq media outlet claimed responsibility saying:"Two Christian priests were killed today, ISIS shot them down."
ICC said the attack happened as three nearly simultaneous car bombings occurred in the city of Qamishli. One of the explosions occurred near a Chaldean church.
Video footage obtained by Hawar News shows that the car the priests were in had a special tag in its front window which showed that it was traveling for business with the Armenian Catholic Church.
Claire Evans, ICC's regional manager for the Middle East, said the tragedy has "deeply wounded the region's entire Christian community".
She added: "Christians have long warned that ISIS will seek every opportunity to continue its genocide against religious minorities. Meanwhile, Turkey's actions in the area have generated an environment of instability.
"Armenian Christians, whose ancestors were killed by Turkey's genocide, find themselves caught between violent actors across all of Syria. We must keep the Christian community of Syria in our prayers, and urge for an end to this senseless conflict."
ISIS was officially declared militarily defeated in Syria this past March. However, retaliation attacks following the October death of ISIS leader al-Baghdadi in Syria have been expected.
ICC said this is the first deadly incident since its military defeat in which ISIS has successfully targeted church leaders in the Levant.
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