By Eliott C. McLaughlin and AnneClaire Stapleton

(CNN) -- Police and the FBI began a third day of digging in a southeast Michigan field Wednesday in hopes of uncovering clues in the cold cases of as many as a half dozen girls who went missing from the Detroit area in the 1970s and 1980s.

While the activity has been unsettling for nearby residents, more unsettling is the reason authorities homed in on this particular field: It's the same area where a convicted child killer buried 13-year-old Cindy Zarzycki after kidnapping and killing her in 1986, Warren Police Commissioner Bill Dwyer said.

Zarzycki's killer and the suspect in the cold cases is Arthur Ream, who turned 69 on Wednesday. He is presently serving a life sentence in Muskegon Heights, in the opposite corner of the state.

"Based on our information, we believe he chose to bury these other teen girls in the same general area," Dwyer said. "I would describe Ream as a serial rapist and killer."

It is not clear if Ream has an attorney, but he faces no charges related to the missing girls.

The field sits along the North Branch Clinton River and is tucked among small residential neighborhoods and two golf courses. It's about 3 miles west of Interstate 94. The field is several miles north of Warren, a Detroit suburb, but Warren authorities are working the case with the FBI and the Macomb County Sheriff's Office.

Footage from the scene showed several vehicles parked in a dirt field along a wood line and two tents set up at the edge of the brush. A backhoe dug up the earth as authorities looked on.

Break in the cases?

News of the search ignited hope among the missing girls' loved ones, but also reopened tender wounds. Kimberly Alice King went missing in 1979, and her sister told CNN affiliate WXYZ that it's been "almost 39 years of agony" for the family.

"As you can imagine, I am both devastated and grateful to be where we are today," Konnie Beyma told the station. "My father is 80 years old. It's time for closure. We need to bring Kimberly home and lay her to rest as she deserves. She's been through enough. She needs to be back with her family."

Dwyer did not provide extensive details on how his detectives came to reopen King's case, other than to say, "Law enforcement at times will open these cold cases and take a second look."

In the course of that second look, detectives interviewed Ream several times in prison, he said. Ream "flunked a polygraph test," and investigators then obtained a search warrant for the field in Macomb County, the commissioner said.

"This is private land and we do not believe the land owner has any involvement," he told CNN.

Dwyer says he wants to bring closure to the families. Brenda Lee Handloser, who was 9 when her sister, Nadine O'Dell, vanished, told CNN affiliate WDIV that closure is all she wants.

"I want to bring my sister home and lay her to rest. I don't care if it's a bone, a piece of hair, a nail. I don't care. I just want my sister," she said.

The girls

Though Dwyer said investigators believe four to six of the girls may be buried in the Macomb County field, he provided CNN with the names of only four of them:

• Kimberly King, who went missing from Warren on September 15, 1979. She was 12 at the time.
• Kellie Brownlee, a 17-year-old who disappeared in Novi, about 30 miles northwest of Detroit, in May 1982.
• Kim Larrow, who was 15 when she vanished from Canton Township, 30 miles west of Detroit, in June 1981.
• Nadine O'Dell, 16, who never showed up at her boyfriend's house in Taylor, southwest of Detroit, on August 16, 1974.

Kimberly was last seen at a friend's house, Kellie at Twelve Oaks Mall and Kim at an ice cream parlor, according to the National Missing and Unidentified Persons System.

Nadine was last seen walking down a road in Inkster, about 20 miles west of Detroit, according to the missing person database. Her boyfriend was supposed to pick her up along the route. He "was on the way to meet her and arrived 20 minutes later and had not crossed paths with her," the database said.

Handloser remembers Nadine's boyfriend returning to the house and asking where she was.

"She wasn't there and that is how it all started," Nadine's sister told WDIV. "I know there is somebody out there that knows. ... I know somebody had to see something. It was during the day."

Arthur Ream's prior

In 1975, Ream was charged with taking indecent liberties with a child and sentenced to five years in prison, according to Michigan Department of Corrections records. In 1996, he pleaded guilty to third-degree criminal sexual conduct with a minor between 13 and 15 years old, the records show.

A judge handed down a 15-year sentence, which Ream was serving when he was implicated in Cindy Zarzycki's murder.

According to court records from a failed 2010 appeal of his murder conviction, Ream knew Cindy through his son, Scott, who was dating the 13-year-old.

Ream had spoken to Cindy on the phone April 20, 1986, and asked her to meet him at a local Dairy Queen for his son's surprise birthday party, the records said. Not only was Scott's birthday in January, but evidence indicated that Ream had arranged for Scott to be out of town that day.

Cindy's brother followed her to Dairy Queen, her friend saw a white van similar to one owned by Ream, the Dairy Queen was located a short drive from the carpet business where Ream was living at the time and Ream's wife refuted his alibi, according to the records.

"A reasonable jury could find that defendant deliberately lured Cindy to the Dairy Queen through the ruse about his son's birthday and that Cindy was never seen again because defendant killed her," the court records stated.

Ream also "indicated he knew the location of Cindy's body and admitted to having a fetish for 13- and 14-year-old girls," the documents continued. Numerous reports indicate Ream drew a map for investigators, leading them to Cindy's body, which was buried in the field authorities have been searching this week. He was convicted of first-degree murder in 2008.

Kathie Lucas held a photo of her sister, Kimberly King, as she told WXYZ this week's search is the best chance for justice in decades.

"We're losing years, either for people who witnessed it, or for the person who did it, to whatever -- just anyone who knows anything that might connect it to," she told the station.

Commissioner Dwyer told CNN he would hold a news conference if any remains were found at the Macomb County property. A news conference is scheduled for Wednesday afternoon, though Dwyer would not say whether the search had yielded any evidence.

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