From Halopedia, the Halo wiki
Sector Six is a location at coordinates 32°53′12″N, 69°27′48″E on Earth in the Pakistan-Afghanistan region,[Note 1] The area is home to several satellite dishes and other UNSC installations, including towers with Surface-to-Air Missile Launchers and a bunker.
During the Battle for Earth on November 17th, 2552, Sector Six was the site of an engagement between the UNSC and the Covenant. Orbital Drop Shock Troopers T. Rymann and S. Hartley were ordered there to retrieve a laser designator and use it to track SPARTAN-117's fall into atmosphere. Unfortunately, the Covenant had a significant presence in the area.
The ensuing battle met with heavy casualties on the behalf of both UNSC Marine and Jiralhanae forces. Bravo-21 was killed by a Jiralhanae Chieftain wielding a gravity hammer, after he flanked a column of Jiralhanae Minors and tried to hold them off with a sniper rifle. Finally, the Marines managed to retrieve the designator, lock onto SPARTAN-117 and escape into a bunker.
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