Former WBO heavyweight champion Tommy Morrison died in an Omaha, Neb., hospital late Sunday night. He was 44.Morrison's longtime promoter, Tony Holden, said Morrison died at 11:50 p.m. with his wife Trisha beside him.Morrison tested positive for HIV in 1996 before a fight with Arthur Weathers, effectively ending his boxing career. In the years that followed, he denied having HIV and also challenged the existence of the virus.Trisha Morrison, who married him in 2011, picked up that fight, and in a recent interview with ESPN.com insisted that Morrison had Guillain-Barre Syndrome, not HIV.Holden declined to comment Monday on the cause of Morrison's death."I don't know what the official cause of death at the hospital will be," he said."You prepare for things like this, and still you feel like you got hit by a truck when you hear the news."