From Halopedia, the Halo wiki
Their base was in the Scyllion Warehouse District. He escaped with Jacob Keyes and the others after the operation turned nasty. During their escape, Smith was burned to death when an Insurrectionist RPG struck near him, and he was hit by several pieces of flaming debris, which set him on fire. Keyes tried to get Smith to roll out the fire, but the ONI operative was burnt to death before Keyes could help.
Smith seems to have been named for a friend of Tobias Buckell, the author of Halo: The Cole Protocol. In the Acknowledgments section of the book, Buckell thanks his friend Josh Smith for getting him to buy an Xbox 360.
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