"Some people say accident, it may be an accident, it may be something else," Museveni said, suggesting for the first time that the July 31 crash of his presidential chopper in which Garang was riding may have been the result of foul play.

"I am looking (at) all options," he told a crowd of thousands of mourning southern Sudanese in Yei where Garang’s body was brought as part of a funeral procession before his Saturday burial in the town of Juba.

"The (helicopter) was very well equipped, this was my (helicopter) the one I am flying all the time, I am not ruling anything out," Museveni said, noting that an international panel of experts had been appointed to look into the crash.

"Either the pilot panicked, either there was some side wind or the instruments failed or there was an external factor," he said. "The inquiry will look at all possibilities."