A District man who fatally stabbed his ex-girlfriend and scribbled “you gave me AIDS” on her apartment wall was sentenced to 50 years in prison Friday.

Keith Littlepage, 51, who was found guilty of first-degree premeditated murder and other offenses in the March 4, 2011, slaying of his ex-girlfriend Selina Knight, repeated before his sentencing — as he had during his summer trial — that he had nothing to do with Knight’s death.

“I loved Selina. I do not know what happened to her,” he told D.C. Superior Court Judge Thomas J. Motley.

Knight, 36, was HIV positive because of a prior relationship, her mother testified during the trial. Littlepage, it was revealed during the trial, did not have the illness.

“Her HIV didn’t turn me away. It drew me closer to her,” Littlepage said in court Friday.

Prosecutors said Littlepage killed Knight because she ended their romantic relationship and kicked him out of her Southeast Washington apartment.

Prosecutors had no witnesses, no weapon and no DNA linking Littlepage to the crime. They relied on the testimony of friends and relatives of the couple who said Littlepage often said he would kill Knight if she left him.

Members of Knight’s family and prosecutors had asked Motley to sentence Littlepage to life in prison.

Assistant U.S. Attorney Robert Feitel said it was the first time he had ever requested some of his decision on the fact that in 1980, Littlepage pleaded guilty to voluntary manslaughter in another woman’s death.He spent about seven years in prison for that offense.