(ABC News Radio) The brother of a popular YouTube firearms and explosives expert, who was murdered at a gun making business, finds it surprising that his brother did not pull out a weapon to defend himself.

Keith Ratliff, 32, was found with a bullet in his head Thursday evening inside FPS Industries, his gun fabrication business near Carnesville, Ga.

“For him not to pull out that gun and try to defend himself, he had to feel comfortable around somebody. Either that or he was ambushed,” his brother, Kelly Ratliff, told ABC News affiliate WSB-TV.

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