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In late 2555, information was obtained from an Automated UNSC Scout Vehicle, Recon-14, deployed by the UNSC Pillar of Autumn which immediately piqued the interests of the Office of Naval Intelligence. Tress was among those who analyzed the signal, which emanated from an area deemed Location 6201. She correctly surmised that the source of the signal had indeed come from the missing fragment of Installation 04.
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