Mr. Kony, who has been indicted on war crimes charges by the International Criminal Court in The Hague, has been hiding in jungles in the Central Africa for years with a band of child soldiers and a harem of child brides. He formed the Lord’s Resistance Army more than 25 years ago with the aim of overthrowing the Ugandan government. He had been on the run in recent years, sought by more than 2,000 Ugandan troops supported by American Special Operations units.
Officials in the Central African Republic have been in contact with members of the Lord’s Resistance Army who are seeking to surrender, though there is little evidence thus far that Mr. Kony is among them. An African Union official fueled speculation about Mr. Kony, saying that the rebel leader had a “serious illness.”
A State Department official said that the United States had been aware for several months that a small group from the Lord’s Resistance Army was in the Central African Republic, but that there were few signs that Mr. Kony was himself a part of that group.
“Many times in the past, Joseph Kony and his senior commanders have used — and we believe will continue to use — any and every pretext to rest, regroup and rearm,” said the official, who spoke on the condition of anonymity, “ultimately returning to kidnapping, killing, displacing and otherwise abusing civilian populations.”
That skepticism is shared by the Ugandan military. “The L.R.A. is not a very reliable partner,” said Lt. Col. Paddy Ankunda, a spokesman for the Ugandan military. “We support the initiative on principle. If they can get serious that’s good, but they’ve never been serious.”
Mr. Kony was the focus of the video “Kony 2012” by the advocacy group Invisible Children, which became a sensation on the Internet last year, bringing mainstream attention to the altar boy turned brutal rebel, who often wore wigs and costumes. His fighters were known for kidnapping thousands of children and brainwashing them into becoming killers themselves, who committed gruesome acts like sawing off lips.
But the Lord’s Resistance Army has been seriously weakened in recent years and many of his followers have defected. The Central African Republic’s president, Michel Djotodia, told Abou Moussa, the special representative and head of the United Nations Regional Office for Central Africa, that he was in contact with Mr. Kony and that he was encouraging him to surrender.
A spokesman for Mr. Djotodia, Guy Simplice Kodegue, confirmed that the president had recently spoken with Mr. Kony, and that he was in the country. He said Mr. Kony had agreed to lay down his weapons.
Kasper Agger, a field researcher for the Enough Project, based in Uganda and focusing on Lord’s Resistance Army, said that “the report has been circulating for some time behind the scenes.” He said that the group was under “unprecedented pressure” between the American special forces and the Ugandan troops involved in the hunt.
Speaking to reporters at the United Nations on Wednesday, Francisco Madeira, the African Union special envoy for Lord’s Resistance Army issues, said that, “Many reports that we have received indicate that he is suffering from some serious illness, some uncharacterized illness.”
Many analysts have long held that Mr. Kony will not give himself up and risk transfer to The Hague. “Having studied the L.R.A., knowing my history, I see no truth that Kony would ever come out,” Mr. Agger said. “I don’t believe it’s in his game plan to come out peacefully.”
Adam Nossiter contributed reporting from Dakar, Senegal, and Rick Gladstone from New York.