GARY, Indiana (WTVD) -- Investigators in several states are reviewing unsolved murders and missing person reports after the arrest of an Indiana man who police say confessed to killing seven women and hinted at more victims over a 20-year span.
Darren Vann, 43, a former Marine convicted of sexual assault in Texas in 2009, was charged Monday in the strangulation death of 19-year-old Afrikka Hardy, whose body was found Friday in a bathtub at a Motel 6 in Hammond, 20 miles southeast of Chicago. He also was charged with murder in commission of a robbery and robbery causing great bodily injury.
CNN reports Vann was arrested on unspecified charges while living in Cherry Point, North Carolina, in 1993.
But determining whether others have fallen prey to Vann could take years, a former high-ranking agent at the FBI's Chicago office said. That some of his alleged victims may have been prostitutes or had fallen through society's cracks could also complicate the investigation.
"It does make it difficult. It indicates he preyed on individuals that might be less likely to be reported missing," said Gary Mayor Karen Freeman-Wilson.
In the Hardy murder, a probable cause affidavit said police identified Vann from surveillance video outside the motel.
Hammond Police Chief John Doughty said Vann confessed to Hardy's slaying and directed police to six bodies in abandoned homes in nearby Gary. Charges in those cases are expected this week.
Police in Gary and Austin, Texas, said they are reviewing missing person reports and unsolved cases to determine whether any might be connected to Vann after he indicated during interviews that he had killed before.
Former FBI agent Joseph Ways Sr., now executive director of the Chicago Crime Commission, a non-governmental watchdog group, told The Associated Press that such investigations can stretch into years. Investigators will trace Vann's footsteps, down to examining gas receipts and toll both records, to learn where he traveled.
Ways said teenagers or adults who maintain close contact with their families are typically reported missing quickly, but that's not always the case for those engaged in prostitution, he said.
"If one of them goes missing for days or weeks, it might be that nobody notices," he said. "It's a shame."
Doughty said Hardy was involved in prostitution and had arranged to meet Vann at the motel through a Chicago-area website. Police were called by someone who attempted to reach Hardy but received text message responses that made no sense and that she believed came from the suspect.
The backgrounds of the other victims weren't immediately revealed.
Police took Vann into custody Saturday afternoon, and during interviews the suspect confessed to Hardy's killing, told investigators where the Gary bodies could be found and hinted at other victims since the 1990s, Doughty said.
"It could go back as far as 20 years based on some statements we have, but that has yet to be corroborated," Doughty said. The Gary slayings appeared to have happened recently, he said.
The body of one victim, 35-year-old Anith Jones of Merrillville, Indiana, was found Saturday night in an abandoned home. She had been missing since Oct. 8.
Five more bodies were found Sunday in other homes. Doughty identified two of the women as Gary residents Teaira Batey, 28, and Christine Williams, 36. Police have not determined the identities of the other three women, including two whose bodies were found on the same block where Jones' body was found.
Austin police on Monday said they would review potential related cases based on information provided by Indiana police.
Vann is registered as a sex offender in Texas, where the Department of Public Safety listed his risk of attacking someone again as "low." He did not register in Indiana.
Court records in Travis County, Texas, show Vann served a five-year prison sentence, with credit for the 15 months he was in jail awaiting trial, after pleading guilty in 2009 to sexually assaulting a woman at an Austin apartment two years earlier.
The woman told police that she went to Vann's apartment, where he asked if she was a police officer. After she told him no, he knocked her down, strangled her, hit her several times in the face and told her he could kill her. He then raped her.
Vann allowed the woman to leave and she called police the next day.
The circumstances of that case had similarities to Hardy's death, according to the victim's mother and court records.
Lori Townsend said police told her that Vann asked her daughter to perform a certain sex act, and "when she said 'no' and put up a fight, he snapped and strangled her."
Vann told police Hardy began to fight during sex and that he strangled her with his hands and an extension cord, the probable cause affidavit says.
"This man is sick," Townsend said from her home in Colorado.