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On September 24, 2517, Dartmouth was en route to Eridanus II. Upon transitioning from slipstream space in the Eridanus system, the ship was intercepted by the insurrectionist frigate Iliad. Despite Dartmouth's crew calling for UNSC support, the rebels managed to board the transport and escape before the UNSC frigate UNSC Journeyman arrived. The Dartmouth's crew armed themselves and attempted to hold the ship against the boarders, but were presumably killed.
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