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United Nations Space Command
The Ark Security Detachment was a UNSC security detachment stationed on Installation 00 prior to their deaths on 11 November 2558.
According to record U-965-B in the UNSC Logistics Database, the detachment had access to M12 Warthog with M46 Vulcan on them.
The detachment also had access to HRUNTING/YGGDRASIL Mark IX Mantis exoskeletons, however most were destroyed in the initial Banished attack.