ATLANTA, Ga -- Police say a man who was found lying behind a tractor trailer Sunday morning in downtown Atlanta had been shot in the head.

The man was discovered by a passing motorist in the I-75 southbound emergency lane near Capitol Avenue around 7:10 a.m., according to police. The 9-1-1 caller was en route to the Atlanta airport and had left the scene by the time police arrived.

The victim was bleeding from the head and was unresponsive when he was taken to Grady Memorial Hospital. Doctors performed a CAT scan on the man, which revealed he had been shot in the head.

Police recovered several shell casings from the scene.

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