- Police say Darren Deon Vann admitted to killing 7 women in northern Indiana
- He was arrested for threatening to burn up his girlfriend in 2004; got 90 days in jail
- Vann was convicted of aggravated sexual assault in Texas for raping, hitting woman
- Authorities later categorized him as a "low-risk" sex offender; he moved back to Indiana
Gary, Indiana (CNN) -- Darren Deon Vann was no stranger to police.
Even before police caught up with him this weekend, Vann's record was well-established. He had gone to jail at least twice before on felony convictions. But -- if authorities are to be believed -- his time behind bars didn't prove much of a deterrent.
Authorities went after the 43-year-old Vann this weekend in connection with the death of 19-year-old Afrikka Hardy at a Motel 6 in Hammond, Indiana. Not only did he confess to that killing, but police said Vann also admitted to six other women's deaths. Police said he led them to the women's bodies in abandoned structures in Gary, Indiana.
"It disgusts me, because it's seven bodies," said Ronnie Williams, a resident of the Gary neighborhood where most of the victims were found.
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Vann had an initial court appearance related to Hardy's killing on Wednesday morning, but was held in contempt of court when he refused to answer the judge's questions.
Vann was represented by a state-appointed public defender, Matthew Fech.
There's much more that's not known publicly about Vann, in fact, than is known. Like, what is his background? What did he do for a living? Why -- if it is proven he killed these seven women -- would he do such a thing?
What is known that Vann was born in Indiana but didn't stay there his whole life. Records, for instance, show he was arrested on unspecified charges while living in Cherry Point, North Carolina, in 1993.
It was in the 1990s that Edward Matlock first got to know Vann. Vann had married Matlock's mother, who was about 30 years older than Vann.
Matlock said he wasn't comfortable or happy with his mother's marriage, which lasted 16 years. Part of it had to do with the age difference between the couple. Then there were Matlock's observations that Vann talked to himself or sometimes seemed lost in thought, in addition to stories he heard about Vann spending time in a rough part of Austin, Texas, where the pair had moved.
"The guy is a nutcase. He is. And I'd watch him," Matlock told CNN's Ashleigh Banfield. "I'd never allow him near my kids or in my home, because he just freaked me out."
Matlock said things "went downhill" for Vann after he got fired from a temp agency, adding he had trouble finding good work after that. Eventually, Vann and Matlock's mother moved from Austin to Gary, Indiana, where Matlock said he found them "living in poverty."
Gary was where Vann had his first major brush with the law: in April 2004, with a woman (who wasn't Matlock's mother) who police described as Vann's girlfriend.
According to a police affidavit tied to that incident, Vann threatened to burn down or blow up the home of a man who he believed was sheltering his girlfriend. Then, in front of police, he "grabbed (his girlfriend) and told the police to back up or he would burn himself and (the girlfriend)," the affidavit stated.
With his left arm around the woman's neck and his right hand holding a gasoline can and lighter, Vann refused her requests for freedom -- right up until police grabbed and arrested him.
Vann was charged with a class D felony, and spent 90 days behind bars after his conviction.
At some point after his release, Vann went back to Austin. That's where, in December 2007, he was arrested again, this time for aggravated sexual assault.
According to the affidavit out of Travis County, a 25-year-old woman responding to "a service call from her employer" met Vann and the two went to an apartment.
After they got inside, "Vann asked her if she was a police officer and she told him that she was not," the affidavit said. "Vann then attacked her."
The court document details how Vann choked, repeatedly struck and raped the woman.
A grand jury indicted him in July 2008. He pleaded guilty and was convicted in September 2009 and sentenced to five years in prison. That led to -- accounting for time served -- his release on July 5, 2013, according to Texas Department of Criminal Justice spokesman Jason Clark.
Again, Vann didn't stay put for long after getting out of jail.
He registered as a sex offender in prison, then told officials there that he would move back to Gary, Indiana. Texas authorities alerted their colleagues in Lake County, Indiana, that Vann was to be considered a "low risk" sex offender, which is based on experts' assessment of the likelihood that a person will commit another sexual offense.
In the 15 months since Vann left Texas, police said, Vann killed seven women, with six of their bodies found in some of the estimated 10,000 abandoned structures in Gary.
There may have been more victims, police said.
After Hardy was found strangled in a Motel 6 bathtub, authorities used cellular phone records to track down Vann on Saturday, along with the blue Jeep he'd been driving. Police said Vann also had Hardy's pink phone and other potentially key pieces of evidence.
Police said Vann confessed, telling them he "messed up" and expressing surprise he had been found so quickly, Hammond Police Chief John Doughty said. A short time later, he led authorities to the six other victims.
Authorities have not detailed what relationship, if any, Vann had with the victims. (In fact, police have only identified four of those killed so far.)
As for why, Doughty said, "I don't have a specific reason he does this."
Vann's next court appearance is scheduled for October 29 at the Lake County jail in Crown Point.
CNN's Poppy Harlow, Eliott C. McLaughlin, Ed Payne, Marina Carver, Sonia Moghe, Stephanie Gallman, Haimy Assefa and Renee Wunderlich contributed to this report.
