A former FBI profiler warns that a potential serial killer in Michigan may have left behind valuable forensic evidence at outdoor crime scenes as authorities investigate whether five deaths in Lansing are connected.
Mary Ellen O'Toole told the " The Big Weekend Show " on Saturday that the killings posed risks for the offender because they occurred outdoors where the victims, all believed to have been homeless, were likely sleeping.
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"It's also very high risk for the offender because the offender comes in to an open area and kills these people — and these are probably not quick homicides — and then has to leave the area."
"And I can almost tell you for sure that this offender is not cleaning up his crime scenes," she added. "So he's probably leaving behind some very valuable evidence for investigators to analyze."
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The five victims were discovered near the Lansing River Trail near Michigan State University. The deaths occurred between October 2025 and September 2026. Police arrested a suspect in connection with the stabbing death of one man, but have not linked him to the other deaths.
O'Toole said police have more work to do before determining whether the cases are related.
That includes examining unsolved homicides in the surrounding area and potentially other states for evidence of earlier crimes by the same offender.
"They'll look at other homicides both in Michigan and in the surrounding areas because we know from other cases serial killers can travel around, so they want to be able to understand the breadth and the extent of the damage that one person could do," she said.
"And in that effort, they'll be looking at what we call practice murders. These are the murders that a serial killer will engage in as they're becoming a lot better at their trade. And those practice murders could have occurred in Michigan or in another state," she added.