Even in a country beset by murder and death, the 16th Brigade represented a new frontier. The brigade, a 1,000-man force set up by Iraq’s Ministry of Defense in early 2005, was charged with guarding a stretch of oil pipeline that ran through the southern Baghdad neighborhood of Dawra. Heavily armed and lightly supervised, some members of the largely Sunni brigade transformed themselves into a death squad, cooperating with insurgents and executing government collaborators, Iraqi officials say. Full Story