A decade before Darren Deon Vann confessed to killing at least seven women in Indiana, he threatened to set himself and a woman on fire during a 2004 standoff with police, according to court documents released Tuesday.
Officials said they feared that the encounter was part of a bloodier trail that the 43-year-old left across at least two states during more than 20 years.
Vann has confessed to killing more than the seven women whose bodies were found since Friday, police said.
Investigators "have concerns" that Vann, who has lived in other states, could have left victims behind before moving back to Indiana, according to FBI Special Agent Robert Ramsey.
"We are looking beyond Lake County and he has been cooperative," Ramsey said, adding that local police had built a "great rapport" with Vann. "He is talking, and what we're looking to do now is to verify some of the information that he has been providing.
"He has made general statements indicating that there may be additional victims," Ramsey said. "That's an area of concern for us that we'd like to address."
Vann was arrested in the fatal strangling of Afrikka Hardy, 19, whose body was found Friday in a bathtub at a Motel 6 in Hammond, Ind. Vann is scheduled to appear in court Wednesday on murder and robbery charges.
He directed police to six more bodies, officials said.
Charges in the deaths of the other women, all found in Gary, could soon follow, Lake County Sheriff John Buncich said. He said police were awaiting autopsies and potentially more evidence.
Vann's first known contact with police was in April 2004 when he was arrested and charged with residential entry and intimidation stemming from an incident in Gary. Police alleged Vann threatened to kill a man in a wheelchair over a $7,000 debt that he believed he was owed by his ex-girlfriend, who was then living with the man, court records show.
According to court filings in that case, the victim told police he saw Vann approaching his house carrying a red plastic gasoline can. The man said he confronted Vann and asked him why he wanted to "burn my family, innocent people over a woman?"
Vann replied, "Give me $7,000 and you can have her," according to the filings. Vann also told the man that he had dynamite and would blow the man up if he didn't give up the woman, court records show.
When police arrived, Vann was "holding a cigarette lighter and was acting crazy as if he might light himself on fire," according to court records.
In a deal with prosecutors, Vann pleaded guilty in June 2004 to misdemeanor residential entry, and the felony charge of intimidation was dropped, court records show. He was sentenced to a year in jail and a year of probation.
In September 2005, Vann admitted violating rules of his probation and he was sentenced to 90 days in jail, court records show.
Vann spent five years in a Texas prison after he was convicted in the 2007 sexual assault of a 25-year-old woman in Austin. Vann was accused of pummeling his victim before forcing her to perform oral sex.
After his release in the Texas assault, Vann moved to Indiana, where he split time living with his sister and in a single-story ranch home in Gary. Texas' sex offender registry classified him as a low-risk offender.
Vann told police he met Hardy through an ad on Backpage.com, according to an affidavit. The sexual encounter became violent, and when Hardy began fighting back, Vann strangled the woman using his bare hands and a cord, he said.
Police in Gary were using trained dogs to search for bodies around the places where other women's bodies were found over the weekend, authorities said.
"I have dispatched a team of officers along with a cadaver dog to the Glen Park and Midtown sections of the city," Gary Police Chief Larry McKinley said. "The purpose of the search is to ensure that the structures are completely vacant, get them boarded up and place them on the list for demolition."
It's unclear when the six women found in Gary were killed. One was reported missing in January.
In addition to Hardy, the police have released the identities of three other victims: Anith Jones, 35, of Merrillville, Ind.; and Kristine Williams, 36, and Teaira Batey, 28, of Gary.