By Opheera McDoom

KHARTOUM (Reuters) - Sudan's army has stepped up security in Khartoum, saying it has intelligence that a heavily armed convoy of Darfur rebels has advanced to the neighbouring Kordofan province and is planning an attack.

But the rebel Justice and Equality Movement denied any move on Sudan's capital and accused the government of trying to distract attention from recent bombing raids on Darfur that hn