CLEVELAND, Ohio - A look at the unsolved murders of more than 60 women dating back to 2004 reveals patterns, ones that could mean some of the cases are connected, according to an analysis done in partnership by The Plain Dealer, Murder Accountability Project (MAP) and WKYC Channel 3.

The unsolved cases have a number of statistically unusual commonalities, especially among the women killed by "hands-on" methods, according to Thomas Hargrove, chairman of the non-profit MAP.

Women who were strangled, stabbed or killed using blunt force skewed older and were more likely to be white or Hispanic. Women with histories of soliciting also were extremely likely to be killed using one of those more personal methods, which are more often used by serial killers.

Hargrove first analyzed the unsolved murder data in partnership with The Plain Dealer in February 2017, after MAP's "serial killer" algorithm indicated the city had one of the nation's largest suspicious clusters of unsolved homicides over the past decade.

At the time, Hargrove pointed out deaths in two geographic areas, along the Euclid Avenue corridor in Cleveland and East Cleveland, and another along East 93rd Street. A third, more widely distributed pattern, involved an unusually high number of unsolved murders of middle age and elderly women.

Those patterns persist, according to an updated analysis in partnership with WKYC that includes new unsolved cases from 2017. WKYC is airing a two-part series on the cases Tuesday and Wednesday.

The analysis doesn't prove Cleveland has or had an undetected serial killer, but the possibility is worth exploring, said Eric Witzig, a retired homicide investigator for the Washington, D.C., Metropolitan Police Department and for the FBI's Violent Criminal Apprehension Program (ViCAP).

Witzig consulted on the analysis, which MAP also shared last year with Cleveland police.

In September, Cleveland announced an effort to try and address some of the city's many unsolved murders by forming a Homicide Review Task Force, with help from the FBI and the Cuyahoga County Sheriff's and Prosecutor's offices.

That task force is looking at many of the cases included on a map that ran with The Plain Dealer's original story, Jennifer Ciaccia, the department's spokeswoman confirmed. It's not yet known whether they've made any connections or gotten close to solving any of the murders.

The FBI also agreed to make its crime analysis capabilities available to the city's homicide unit, which at the time was considered by many to be understaffed with only 13 detectives.

A month earlier, Mayor Frank Jackson at a press conference called "unacceptable" the rate at which city homicide cases were solved.

The task force was a way to put more resources into solving cases, both old and new, officials said.

Officials also promised the city would increase staffing in the city's unit, although no exact numbers were shared, and to improve methods of investigating murders based on research from across the country.

Jackson said the city had solved only 47 percent of its homicide cases for 2017, which was similar to the number it reported solving to the FBI in 2015. (The number reported to the FBI as solved for 2016 was far lower: 15 percent.)

In decades past, the solve rate was 75 percent or higher, according to FBI records.

Though the murder solve rate has declined, it is unlikely the drop is as steep as it looks. Cleveland, for a time, was not consistently reporting information on the murders it had solved to the FBI. (This was a problem in other cities as well. Read a MAP analysis of the problem here.)

The Plain Dealer last year requested data from the city on the number of homicide cases that were solved or "cleared."

Information the homicide unit provided in response to that request showed that the unit cleared 60 percent of the 133 homicides in 2016.

That includes cases where police made an arrest, cases where a suspect died and ones that were cleared by "exception," meaning an arrest wasn't made but police had identified a suspect and considered the crime solved.

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