Army troops from the 29th Chemical Decontamination Company backed several trucks onto LST-353 at 3:08 p.m. on May 21, 1944. The soldiers were moving 4.2-inch mortar ammunition from a smaller craft onto the ship's elevator. None had received training in handling explosives. The sudden blast killed everyone near the bow. No witnesses survived to explain what triggered the detonation. A fireball erupted from the ship's forward section. Burning debris showered across West Loch at Pearl Harbor.