The rebels are thought to number about 15,000.
At least some of the Chadian rebels are thought to receive Sudanese backing, and some Sudanese rebels contributing to the violence in Darfur receive Chadian support.
Investigators scoured records for infants handed over to social workers in San José del Guaviare, a FARC stronghold in southeastern Colombia near where the rebels are thought to hold their captives, eventually finding a boy named Juan David Gómez Tapiero.
During the past two years the Ugandan army has deployed 4,000 troops in Operation Lightning Thunder to chase the LRA out of Uganda into the Democratic Republic of the Congo, South Sudan and now into the Central African Republic where, 800 miles from its original area of operation, the rebel group is thought to have fewer than 300 followers.
While the United Nations has documented abuses by both Mr Assad's forces and the rebels, the new evidence is thought to be more detailed than anything yet to emerge from the 34-month crisis.
From 2003 to the end of 2008, Unicef recorded more than 6,000 cases of child recruitment by the rebels but the number is thought to have soared in the final months of the war.
The death toll from the rebels' six-year insurgency is thought to be approaching 4,000, but the uncertainties inherent in guerrilla warfare have been intensified by restrictions on journalists' access to the battlefields.
Even Moktada al-Sadr, the rebel Shiite cleric whose militia is thought to be responsible for many of the attacks on liquor stores, condemned the bombings.
Similarly, the US-facilitated proliferation of small arms to rebels in Libya's civil war is thought to be fuelling conflict in Mali and North Africa as these weapons have been transferred into the hands of jihadist groups.
It is thought that the rebels spared the hospital from destruction because they were afraid of catching Lassa fever.
