Small Arms Survey published in May 2014 a lengthy report titled "Following the Thread: Arms and Ammunition Tracing in Sudan and South Sudan" by Jonah Leff, director of operations at UK-based Conflict Armament Research, and Emile LeBrun, consultant on small arms and light weapons issues.
The study concludes that older weapons from the eastern bloc and Iran, as well as newer weapons from China, predominate among all armed actors in Sudan and South Sudan. Sudanese security forces are the primary source of weapons to non-state armed groups in Sudan and South Sudan through deliberate arming and battlefield capture. Khartoum's deliberate supplying of Chinese manufactured arms and ammunition to southern insurgents took place in apparent violation of end-user agreements with the government of China.
As Sudan has bolstered its arms manufacturing sector since the 1990s, Sudanese military equipment has increasingly appeared on the battlefield and in the hands of non-state armed groups. Sudanese-manufactured ammunition proliferates not only in Sudan and South Sudan, but also in other conflict zones such as the Central African Republic, Cote d'Ivoire, the Democratic Republic of the Congo, Somalia, and Syria.
The government of South Sudan and southern insurgent groups have supplied arms and ammunition to civilians in South Sudan. South Sudanese armed groups are in possession of an increasing number of weapons whose factory marks and serial numbers have been removed, a tactic designed to undermine identification and tracing.