(Sketch of suspect, provided by police)

Flint police are investigating whether a stabbing attack early Saturday morning is related to a suspected serial killer who has killed five people and wounded eight others since May.

The man stabbed Saturday was reportedly in critical condition. He walked into a Flint hospital after the attack.

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Speaking live on WWJ Saturday afternoon, WJRT-TV reporter Lori Dougovito said there were some discrepancies in the new case which led investigators to believe the stabbing may not be connected to the serial killer.

Messages to Michigan State Police and Genesee County Prosecutor David Leyton were not immediately returned Saturday.

Survivors have described their assailant as a muscular, young white man, and all but one of the 13 victims was black, Flint Police Lt. T.P. Johnson told The Associated Press Friday.

The suspect is in his 20s or 30s, and weighs 180 to 210 pounds. Police also say he usually wears a baseball cap during the attacks.

He is typically attacking people with small frames who are between the ages of 17 and 60, police said.

Flint is a predominantly black city, and investigators are unsure if the suspect was targeting blacks or whether the victims were chosen at random.

 The victims were all outside alone at night. Survivors have said the attacker approached them under the pretense of needing directions or help with a broken down vehicle.

“He then pulls a knife and attacks them without saying anything more,” Johnson said.

“A knife is a very personal weapon. To stab somebody repeatedly, there has to be some rage going on,” he said.

Detectives have been investigating the attacks since they started, but a pattern only became apparent on Tuesday, a day after 49-year-old Arnold Minor was found slain along a Flint street, Johnson said. That led to the announcement that a serial killer might be on the prowl in the working class city ravaged by economic turmoil, budget problems and police layoffs.

Michigan State Police are leading a task force investigating the attacks. Ten have been in Flint, about 50 miles northwest of Detroit. Three others were in nearby communities.

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On July 30, the body of 60-year-old Frank Kellybrew was found not far from the Flint Township motel he had called home for about 10 months.

A Michigan State Police task force now is leading the investigation.

Johnson suspects the attacks might be racially motivated. He said the attacker seeks out smaller black men at night after asking for directions or help with car trouble.

What motivates someone to become a “serial killer”?

WWJ Newsradio 950’s Marie Osborne spoke, Friday, with local psychiatrist, Dr. Barbara Herzig Belkin.  She said there is a typical serial killer profile.

“Typically they are single white makes. And, some of them, can be actually quite charming, and they have their own set of rules that they have created for themself,” Dr. Belkin said.

Dr. Belkin, who has worked with serial killers, said they are often hard to catch because they often are highly intelligent and are loners. She says that often times they are anti-social or narcissistic.

“More than anything, typically they lack empathy or guilt,” she said. 

“Not all of them always have a psychotic disorder,” Dr. Belkin said.

Dr. Belkin said it appears the Flint serial killer is mission oriented — someone who believes they need to rid the world of a certain type of person.  

Anyone with information is asked to call Flint Police at (810) 732-1111.

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(Copyright 2010 WWJ Radio.  All Rights Reserved. The Associated Press contributed to this report)