Hadith.485 - Imam Jafar ibn Muhammad Al-Sadiq عليه السلام said:
“If a man is found killed and one of his limbs is found intact, a funeral prayer should be offered over it, and it should be buried. If no complete limb is found, no funeral prayer is offered, but it should still be buried”.
And if a man is cut in half, he should pray funeral prayer over the half that contains the heart; if only the head remains, he should not pray funeral prayer over it.