Unsolved: Did serial killer Israel Keyes have a link to the Alexis Patterson case?

Alexis Patterson disappeared on her way to Hi-Mount School in Milwaukee on May 3, 2002.

She was 7.

The latest season of Unsolved, a true-crime podcast for USA TODAY and the Milwaukee Journal Sentinel, examines the case. The episodes feature exclusive interviews with Alexis' family and more details about the police investigation than has ever been public. Unsolved is available on all podcast platforms.

During the making of Unsolved, a possible connection emerged between Alexis Patterson and a serial killer named Israel Keyes. Here's what to know:

Who is Israel Keyes?

Keyes was from Alaska. He confessed to murdering eight people, although authorities believe he is responsible for 11 killings between 2001 and 2012.

Israel Keyes is seen in undated booking photos.
Israel Keyes is seen in undated booking photos.

Where did his crimes take place?

The killings happened across the country, from Alaska to Vermont to New York. Investigators say Keyes stashed so-called "kill kits" in different parts of the country, sometimes years in advance. The kits contained supplies such as weapons, shovels, plastic bags and bottles of Drano.

How did Keyes get caught?

Keyes was arrested in 2012 when authorities were investigating the disappearance of 18-year-old Samantha Koenig from Anchorage, Alaska.

Keyes posted a ransom note and used Koenig's ATM card, which led police to Lufkin, Texas, where he was arrested. Koenig's body was found in a frozen lake in Alaska three weeks after his arrest.

What is Keyes' connection to Alexis Patterson?

After Keyes was arrested, the FBI took his laptop and his girlfriend's computer and examined the devices. They found Keyes had been looking up missing people. He used the online database called the National Missing and Unidentified Persons System, NAMUS.

One of his search results was Alexis Patterson.

Josh Hallmark, creator and host of the podcast "True Crime Bullsh**," was the first to report that. The title of his podcast comes from a statement Keyes made to the FBI, that he didn’t want his case to get a lot of media attention.

Alexis Patterson was 7 when she disappeared as she was headed to school in May 2002.
Alexis Patterson was 7 when she disappeared as she was headed to school in May 2002.

Did Keyes have other links to the Alexis Patterson case?

Hallmark said Keyes did have a kill kit in Wisconsin. He also had a red truck.

In Milwaukee, some witnesses reportedly said a red truck was spotted near Hi-Mount School in the weeks before Alexis disappeared, and that a person inside the truck tried to take a child from the playground.

Could Keyes have abducted Alexis Patterson?

Hallmark, an expert on Keyes, does not think so.

For one, Keyes stayed away from major cities. And Keyes told the FBI that after he had his own daughter he could not target children anymore. At the time Alexis disappeared, Keyes' daughter was about a year old.

Missing: What happens when a child disappears in America?

The truck Keyes owned was a vintage model, and all evidence points to him not using the truck in 2002, according to Hallmark.

"I just don't see him going in broad daylight to a school in a major city to abduct a child," Hallmark says on Unsolved.

What happened to Keyes?

Keyes died by suicide at a jail in Anchorage while awaiting trial in the Koenig case.

Learn more about the Alexis Patterson case by listening to the true-crime podcast Unsolved.

This article originally appeared on USA TODAY: How serial killer Israel Keyes was linked to Alexis Patterson