Mangum, 32, allegedly stabbed live-in boyfriend Reginald Daye, 46, during an April 3 argument. According to Durham, N.C., police, Mangum stabbed him in the torso with a kitchen knife. He was taken to Duke University Hospital and treated for serious injuries. Daye died Wednesday evening, according to police.
"More than likely, we will be upgrading the charge to murder," Durham Police Chief Jose Lopez Sr. told The Herald Sun of Durham Wednesday.
During a 911 call, a man requesting an ambulance to the residence said Mangum was the attacker. "I told him she was trouble from the very beginning," the man said.
A man who said he was the victim's cousin told ABC affiliate WTVD that Mangum and the victim had a brief relationship.
"I mean he was excited," the man said. "He was like, 'Man, guess who I'm dating now.' He was excited, but I told him, 'Man, you know her background. Be careful.'"
Mangum is currently being held in jail on a $300,000 bond and charged with assault with a deadly weapon with intent to kill.
In February 2010, Mangum was arrested and charged with attempted murder, arson and child abuse after an argument with Milton Walker, then her boyfriend. According to police, she attacked Walker and set his clothes on fire in the bathtub while three children were present. She also allegedly told Walker "I'm going to stab you [expletive]!" in front of officers.
She was found guilty in December of three counts of child abuse, injury to personal property and resisting a public officer. She was sentenced to 88 days in jail, which she had already served while awaiting trial. The felony arson charge was dismissed.
In 2006, Mangum accused three Duke lacrosse players of raping her at an off-campus party. She and another dancer had been paid to perform for the team. Her story was eventually found to be false and a year later charges against the players were dropped.
In 2008, she graduated from college with a degree in police psychology and released a memoir titled, "That Last Dance for Grace: The Crystal Mangum Story."