Northern Ugandan rebel leader Joseph Kony has told mediators that his deputy Vincent Otti is alive but under arrest.
Vincent Otti is wanted by The Hague for war crimes
The Lord's Resistance Army's second in command has not been seen in weeks and there has been speculation that he was killed during a power struggle.
But a northern Ugandan politician and peace negotiator, Norbert Mao, told the BBC that he has spoken to Mr Kony, who denies killing the LRA commander.
He said Mr Otti is under arrest, accused of being a government spy.
Mr Kony and Mr Otti are two of four LRA commanders wanted by the International Criminal Court (ICC) for war crimes committed during their 20-year insurgency.
They remain in hiding in the remote north-east of the Democratic Republic of Congo.
The LRA were notorious for mutilating victims and kidnapping children to be fighters, porters and sex slaves but peace talks over the last year in southern Sudan have raised hopes that the conflict may be over.
Earlier this week, a Uganda army spokesman, Lt Chris Magezi, had told the BBC that Mr Otti and his wife and children were killed weeks ago.
Mr Mao, chairman of Gulu district, has been a key player at the talks and has previously met Mr Kony in his jungle hideout.
"Joseph Kony confirmed to me that they have had internal disagreements and therefore those denying these are lying," Mr Mao told the BBC's Network Africa programme.
"He then said he had not ordered the execution of anybody only Vincent Otti is under arrest."
Mr Mao said the LRA leader claimed that Mr Otti was being used by the Uganda government to undermine him and this forced him to order his arrest.
An LRA spokesman visiting Uganda, Martin Ojul, has consistently denied rumours of a split in the LRA leadership and has said that Mr Otti was suffering from cholera.
Mr Ojul is currently leading an LRA delegation in an unprecedented six-week authorised visit to northern Uganda, including visiting refugee camps, to meet some of the victims of the conflict.
Mr Mao advised the chief mediator at the talks, south Sudan's Vice-President Riak Machar, to send a team to Garamba National park in DR Congo in an effort to resolve the crisis.
On Thursday, the southern Sudanese government had already assembled a team to go DR Congo to find out what had happened to Mr Otti.
Mr Mao said Mr Ojul's team along with some mediators plan to visit the LRA base in Dr Congo after the consultations in northern Uganda are completed, so it will only be matter of time before the truth about Mr Otti is known.