Around 3 a.m., officers responded to a stabbing at a home in the 3000 block of Century Oaks Drive.
When police arrived, they found a 47-year-old man stabbed in the chest.
A man who called 911 identified Mangum as the attacker.
"I told him she was trouble from the very beginning," said the caller.
The stabbing victim - who police have not identified - suffered serious injuries and was taken to Duke University Hospital for treatment.
Investigators say the man is Mangum's boyfriend and say they believe the stabbing occurred during an argument at the apartment the couple shared. According to arrest warrants, Mangum stabbed the man repeatedly.
A man who claims he's the victim's cousin told ABC11 that Mangum and the victim had a brief relationship.
"I mean he was excited," said the man. "He was like, 'man, guess who I'm dating now.' He was excited, but I told him 'man, you know her background, be careful, you know what I mean.'"
Mangum, 32, was later arrested at a nearby apartment and charged with assault with a deadly weapon with intent to kill inflicting serious injury.
On Monday morning, the victim's wounds still had him in the hospital, while Mangum faced a judge.
The judge set Mangum's bail at $300,000.
Her supporters -- including former Durham school board member Jackie Wagstaff -- were also at the hearing.
"Due to the fact that she has never failed to come to court, despite her notoriety in the community, but ma'am, these are very serious charges," District Court Judge Nancy Gordon said.
"We still live in a country where you're innocent until proven guilty," Wagstaff said. "I don't think she's a flight risk, but the law is the law and bond is, I guess, set based on circumstances."
Mangum made national headlines in March 2006, when the then NC Central student and exotic dancer claimed three Duke Lacrosse players sexually assaulted her during a performance at a team party inside a house near Duke's campus.
A year later, Attorney General Roy Cooper dropped all charges saying there was no credible evidence and that the three former players were victims of a tragic rush to accuse.
Former D.A. Mike Nifong was later disbarred and was accused of withholding DNA evidence that would have cleared the players.
Mangum went into hiding, then graduated from NCCU in 2008 with a degree in police psychology. Later that year she released a memoir, "The Last Dance for Grace: The Crystal Mangum Story".
Then last year, Mangum was arrested and charged with attempted murder, arson and child abuse after a domestic dispute with her ex-boyfriend - a different man than the person involved in the incident Sunday.
In December, the jury found Mangum guilty of child abuse, but they couldn't agree on a first-degree felony arson charge, which could have landed Mangum in jail for seven years.