Uganda's army has confirmed the announcement from the US that American and African Union forces in the Central African Republic are holding Dominic Ongwen, a top commander of the Lord's Resistance Army (LRA) who is wanted by the International Criminal Court.

Recruited by the LRA as a child, Ongwen has allegedly served as an aide to the guerrilla group's leader Joseph Kony and is wanted for crimes against humanity, with charges that include murder and enslavement. In a 2005 arrest warrant, the ICC noted that Ongwen was a key member of the LRA's "Control Altar," the core leadership responsible for "devising and implementing strategy, including standing orders to attack and brutalize civilian populations." Reports emerged in 2005 alleging that he had been killed, but were disproved following a DNA test.

"We can now confirm he's the one and we can also confirm he's in our custody at our base in Obo," Paddy Ankunda, Uganda's military spokesman, said on Wednesday. "We think he was just tired of bush life and simply turned himself in."

"His surrender puts the LRA in the most vulnerable position. It is only Kony left standing," Ankunda told AFP, adding that he had first surrendered to CAR's Seleka rebels, before being handed over to US forces.

He added that they were not sure what would happen to Ongwen next, saying, "we are working out procedures."

The US State Department has been offering a reward of up to $5 million for any individual who furnished information leading to his arrest, transfer, or conviction. The same figure is offered for information on Kony, who is also wanted by the ICC for 33 counts of war crimes and crimes against humanity for his connection to guerrilla warfare carried out largely in Uganda, but surrounding countries as well.

The US first announced on Tuesday that a person claiming to be the commander had surrendered in the Central African Republic. However, according to Reuters, Seleka rebels in the country say that they captured Ongwen during fighting, and proceeded to hand him over.

Kasper Agger, a Uganda-based field researcher for the Enough Project who works with LRA escapees, told VICE News he had heard reports that Ongwen wanted to surrender for a while, but feared the indictment by the ICC. Agger speculated that there is a possibility Ongwen fell out with Kony and was forced to run, as has happened before with other top commanders. Agger also said Ongwen was seriously wounded a year and a half ago, something which could have played a part in his decision to leave.

Ongwen's case has long been debated by those who must deal with the complexities surrounding the LRA conflict. Born in 1980, he was about 10 when he was abducted on his way to Koro Abili Primary School, where his parents had transferred him so he could benefit from a wider range of educational opportunities. Ongwen is reportedly not his real name — the likelihood of kidnapping in his region was so great that children were taught from an early age to lie about their personal details if taken. However, once trained as a child soldier, Ongwen was allegedly praised for his loyalty, zealousness and for the violent acts he was willing to commit.

In their field note on him, the Justice and Reconciliation Project (JRP) — an organization based in Gulu, northern Uganda — said that Ongwen's case "raises vexing justice questions."

"What agency is available to individuals who are raised within a setting of extreme brutality?" they asked.

In a 2009 research article published in the Journal of Modern African Studies, Erin Baines described Ongwen as "at once victim and perpetrator," and added: "Ongwen represents a troupe of young rebels who were 'bred' in the shadows of illiberal war economies."

During a seven month investigation, the JRP found that Ongwen was one of eight children born to two school teachers in the Gulu District. They said escapees told them how Ongwen was praised by Kony, who they said called him a "role model" for abducted children. Former LRA child soldiers described Ongwen as being loyal, courageous, and completely "without mercy."

By the age of 18 he was allegedly a field commander and Lieutenant, and he continued to rise through the LRA's ranks. Witnesses report seeing him rape, beat, torture, and execute civilians.

In 2012 IRIN News interviewed Florence Ayot, who said she was forced to be Ongwen's "wife," and subsequently had four children with him.

"We lived like wild animals. We were always on the move. We were running up and down every time to avoid attacks from government forces. I feared for my life. I knew I would be killed one day as the battles continued. But as a commander's wife, I was heavily guarded and had no chance to escape," Ayot said.

After hearing that Ongwen was in US custody, several former LRA child soldiers told AFP that they thought it was important that the LRA commander be prosecuted.

"None of the commanders should be pardoned… Ongwen should be brought to see the terrible things he and Kony did to us," 37-year-old Richard Ojwang, who now works as a carpenter, said. "They abducted us and forced us to fight, the LRA killed my parents and friends."

Charity worker Susan Amoding, who grew up in Gulu, told AFP that what was done to her was unbelievable, as were the things she witnessed.

"They should be punished," she said. "The LRA cannot compensate us for the suffering they inflicted when they abducted us, but the top commanders must be held personally responsible."

Agger said that Ongwen's surrender plays into the bigger picture of the LRA as "an increasingly beaten rebel group with very little objectives."

He said that the LRA has gone from wanting to defeat the Ugandan government to struggling to survive. "Now they have difficulties finding food, finding ammunition, so for them the LRA is not as exciting as it used to be," he explained.

Aggar also noted that Ongwen could give US and Ugandan authorities vital information that could prove game-changing, particularly if he shares details about the group's trade in goods and minerals — thought to be essential to their survival. "We could ask whether he has any information on where these trades are happening so that the supply lines can be cut off," he said.

Furthermore, Aggar speculated, there is a chance that Ongwen's knowledge could lead to Kony's capture.