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Colonial security ships are vessels that transport prisoners between Colonial jurisdictions and are manned by members of the Colonial Fleet.
As with any self-respecting security ship, this ship has cells, its share of armed personnel, a command center, and a rec room where its crew can socialize.
Security ships have facilities capable of launching and supporting Vipers, Raptors and other escort craft, with two landing bays on each side of the ship.
One such security vessel is used to escort Darja Purat from Luna Three to an undisclosed location. However, due to the treachery of Christa Nolan, she and Purat are able to escape (Battlestar Galactica: Season Zero 3).