Hamas armed wing member dies "when a bomb he was guarding exploded accidently"

Do all Hamas bomb-storage sites have armed wing members "guarding" them? I wonder what they are being "guarded" from? Appropriation by armed wings of other "factions"? Anyway, congratulations to his family for a successful and relatively effortless martyrdom operation:

A member of the armed wing of Gaza's ruling Hamas movement died when a bomb he was guarding exploded accidently, the Palestinian militant group said on Friday.

The victim, Majed Khalout, was killed when the bomb exploded as he was patrolling the site where it was stored, the Ezzedine al-Qassam Brigades said in a statement. [...]