French Maxime Hauchard, appeared in a sickening video alongside the masked Briton – real name Mohammed Emwazi - in which he beheaded a Syrian soldier.
Hauchard, who is still thought to be in Syria or Iraq, was in contact with Kermiche before he slit the throat of 85-year-old Father Jacques Hamel. Terror experts believe he could have acted as a mentor to the 19-year-old.
The elderly Catholic priest was taking mass at Eglise Sainte-Therese, in Saint-Etienne-du-Rouvray in Normandy when he was murdered.
The attack on Tuesday bore chilling similarities to the grisly method of murder used by Emwazi and his cohorts in ISIS execution videos.
Hauchard, himself a former Catholic and who is from the same region of Normandy as Kermiche, was part of a group of bloodthirsty ISIS executioners who were guided by Emwazi.
He appeared in a 16-minute video in 2014, lining up beside the west London militant and 19 others as they marched handcuffed prisoners to a secluded spot, grabbing knives from a box on the way. The Syrian prisoners, captured opposition fighters, were then beheaded.
Hauchard, 24, travelled to Syria in 2013 under the guise of a humanitarian mission and was known to French security services as far back as 2011, Express reported.
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