Just for clarity; the article does not say he was hit with a hammer. It says he was hit with a hammer or a box of screws.
The only thing it says he was hit with for sure was screws in the back, and the metal cap in the head causing extensive bleeding.
As presented, the hammer is speculation and only 50% probable as the screws represent the other 50%
And the metal cap in the head was a direct result of him choosing to run back and escalate the encounter.
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