Or if anyone is holding a stone and strikes someone a fatal blow with it, that person is a murderer; the murderer is to be put to death.
NIV
And if he struck him down by throwing a stone, by which a person may die, and he died, he is a murderer; the murderer shall surely be put to death.
AMP
And if he smite him with throwing a stone, wherewith he may die, and he die, he is a murderer: the murderer shall surely be put to death.
KJV