Story highlights Second female torso discovered in Niagara Falls in nearly three years

New York cops: Similarity of victims, killings difficult to overlook

(CNN) Two slayings in Niagara Falls, New York, that investigators Tuesday called "shocking to the conscience" have police wondering whether they have a sadistic serial killer on their hands.

The crimes occurred nearly three years apart, but the circumstances are as similar as they are gruesome: two women, similar in appearance and related to one another through marriage, found dismembered.

The first was 30-year-old Loretta Gates, whose remains were found in areas of the city in September 2012, according to CNN affiliate WKBW . And then last month, the headless, limbless torso of 46-year-old Terri Lynn Bills -- a woman "was like an aunt to Gates," according to WKBW -- was found in an abandoned home.

"You can't overlook that the two homicides share a lot of similarities," Niagara Falls Police Capt. Kelly Rizzo said Tuesday. "It is hard not to make that connection." But he cautioned the crimes could have been committed by two individuals.

Stymied by a lack of breaks in the case (bones discovered Monday on the shores of Lake Ontario turned out not to be human) and frustrated by erroneous leads conjured up and repeated on social media ("social media makes crime investigation incredibly difficult," lamented Rizzo), nearly 100 investigators went door to door in targeted areas Tuesday in "the largest mission of its kind in the history of Niagara Falls."

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