United States forces in Central Africa have taken into custody a man claiming to be a top member of Lord's Resistance Army, the US government said Tuesday, saying the defection could be a “historic blow” to Joseph Kony's command structure.

The man surrendered to US military personnel in the Central African Republic, State Department spokeswoman Jen Psaki said. The man said he was an LRA defector and later identified himself as senior commander Dominic Ongwen.

Ongwen is considered by some to be Kony's deputy commander. He is wanted by the International Criminal Court on war crimes and crimes against humanity. Kony's rebellion, which began in Uganda, is accused of some of the world's worst atrocities including mass killings and keeping girls as sex slaves.

Speaking to reporters in Washington, the US State Department spokesperson noted that the US has not finished establishing “full and positive identification” of the defector, but noted, “If the individual proves to be Ongwen, his defection would represent a historic blow to the LRA's command structure.”

Ongwen is being held in the eastern town of Obo in the Central African Republic, Ugandan Army spokesman Paddy Ankunda told The Associated Press. He said that with Ongwen's defection, only Kony would remain at large among five LRA commanders charged by The Hague court almost a decade ago.

File photo: A member of the US Army Special Forces speaks with troops from Central Africa and Uganda, in Obo, Central African Republic, 2012 (AP/Ben Curtis)