Numbers 35:16 in the King James Version
And if he smite him with an instrument of iron, so that he die, he is a murderer: the murderer shall surely be put to death.
Context
15 These six cities shall be refuge for the children of Israel, for the stranger, and for the foreigner living among them, that everyone who kills any person unwittingly may flee there.
16 “‘But if he struck him with an instrument of iron, so that he died, he is a murderer. The murderer shall surely be put to death.
17 If he struck him with a stone in the hand, by which a man may die, and he died, he is a murderer. The murderer shall surely be put to death.