Deuteronomy 27:24
"Cursed be he that smiteth his neighbour secretly. And all the people shall say, Amen."
Cross References (ranked by relevance)
Moreover ye shall take no satisfaction for the life of a murderer, which is guilty of death: but he shall be surely put to death.
And he that killeth any man shall surely be put to death.
Now Absalom had commanded his servants, saying, Mark ye now when Amnon’s heart is merry with wine, and when I say unto you, Smite Amnon; then kill him, fear not: have not I commanded you? be courageous, and be valiant.
Thou shalt not kill.
And when Abner was returned to Hebron, Joab took him aside in the gate to speak with him quietly, and smote him there under the fifth rib, that he died, for the blood of Asahel his brother.