Foreign Policy published on 6 September 2016 an article titled "Dinner, Drinks and a Near-Fatal Ambush for U.S. Diplomats" by Colum Lynch.
This is an account of an incident that took place on 7 July in Juba near the presidential residence when a convoy of American diplomats travelling in armored cars were fired upon multiple times by members of the Presidential Guard. While the diplomats were probably not targeted by the government troops, the incident raises the question whether Salva Kiir has control over his troops.