The weapon strikes were kinetic and not explosive, designed to sink but much less deadly to crew [View all]
"Limited Crew Kill: Unless the projectile directly strikes a crew member or a critical, volatile area (like an ammunition magazine or fuel tank), casualties are generally limited to the immediate path of the projectile and potential spalling in the immediate vicinity. The damage tends to be highly localized compared to the widespread effects of an explosion. A near miss with a pure KE weapon does zero damage"
"Modern anti-ship missiles predominantly use high-explosive blast fragmentation warheads because they are optimized for creating the maximum amount of general, mission-disabling destruction, including widespread crew incapacitation and death, fires, and systems failure. While a kinetic weapon guarantees a "hard kill" of whatever it directly hits, an explosive warhead spreads lethal effects over a far wider area, which is more effective for killing or incapacitating the ship's crew and systems."
So the primary goal was to sink the boat, that was achieved in the first strike, this was clearly an execution/murder
The Navy's choice of weapon was less lethal, explosive weapon would have achieved both on the first hit