Fugitive Ugandan warlord Joseph Kony is constantly changing his hideouts as the African Union prepares to expand a U.S.-assisted manhunt for one of Africa’s most wanted men, a senior U.N. official said on Friday.Kony has evaded the region’s militaries for nearly three decades, kidnapping tens of thousands of children to fill the ranks of his Lord’s Resistance Army and serve as sex slaves as he moves through the bush. Thousands have been killed by his brutal army.The deployment of U.S. special forces as advisers to help Ugandan soldiers track Kony and his senior commanders in the dense equatorial jungle across a region that spans several countries has raised hopes the sadistic leader’s days are numbered.Three other African countries - the Democratic Republic of Congo, South Sudan and the Central African Republic - prepare to join an African Union guerrilla coalition to launch an international manhunt to capture Kony and see that he is put on trial. Kony appears to be increasingly nervous as a result."The latest we’ve received so far is that, contrary to what Kony used to do - to stay one month, two months on the ground - he’s now moving almost every other day, which means the pressure is mounting on him,” said Abou Moussa, head of the U.N. Regional Office for Central Africa.