LRA deputy Otti is dead, Sudanese official says

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JUBA, Sudan, Jan 23 (Reuters) - Vincent Otti, the deputy commander of Uganda's Lord's Resistance Army (LRA) rebels, is dead, the vice president of south Sudan said on Wednesday.

The statement by Riek Machar, who is mediating talks in Juba between the rebels and the Ugandan government, was the first authoritative announcement of Otti's death following unconfirmed reports that he had been killed late last year.

"I was officially informed by (LRA leader) Joseph Kony that Vincent Otti is dead," Machar told reporters in Juba, south Sudan's capital.

Numerous LRA deserters have said that Kony, whose 20-year rebellion killed tens of thousands of people and uprooted 2 million before a ceasefire last year, shot dead his number two last October, after accusing him of spying for the government.

Machar did not confirm the cause of Otti's death.

Otti, regarded as the brains behind the group in contrast to the volatile Kony, was a prime mover behind the LRA joining peace talks that began last year in Juba. LRA spokesman Godfrey Ayoo said he would make a statement shortly.

Kony has also dismissed his chief peace negotiator, accusing him of profiting from talks with the government, an official said, raising fears of a wobble in the peace process.

"The chairman of the LRA has with disgrace dismissed Martin Ojul the leader of the LRA peace team ... who he accuses of making money from the peace process and intentionally delaying it," David Matsanga, who replaced Ojul, told Reuters by phone.

Two weeks ago, Uganda's Sunday Monitor published an article saying President Yoweri Museveni had given a $200,000 gift to Kony's negotiators, which reportedly angered the rebel leader.

The Uganda government has given Kony until Jan. 31 to sign a deal or risk a returning to war. Machar said he was confident a deal would be reached soon, but did not commit to a time frame.

"Most of the issues have been resolved, what remains is a protocol ... on the implementation modalities and the other two issues; DDR (disarmament, demobilisation and reintegration) and a ceasefire are technical and can be resolved in a short while," he said. (Additional reporting by Francis Kwera in Kampala, writing by Helen Nyambura-Mwaura; Editing by Giles Elgood)