Soon after the media reported Friday that a St. Louis-area boy who had been missing four days was found — along with a teen who had been missing four years — people all over the country took up the case.

Those cybersleuths, most without even a hint of police training, began searching the Internet for information about the man who is accused of kidnapping Ben Ownby, missing since last week, and Shawn Hornbeck, who disappeared in 2002.

They searched sex offender registries across the nation for the suspect's name, Michael Devlin, and gathered all sorts of news articles and other information off the Web.

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By late that afternoon, a blog operated by Steve Huff, CrimeBlog.US, was linked to the personal Web page of a "Shawn Devlin" of Kirkwood — and a comment written on the guest book of ShawnHornbeck.com in December 2005.

"How long are you planning to look for your son?" wrote "Shawn Devlin" on Dec. 1, 2005.

• Click here for "Shawn Devlin"'s personal page.

Several hours later, the same person posted again to apologize for what he had written.

The armchair detectives have access to a variety of crime blogs where they can become involved in their own way with the crime of the day. Opinions and conjecture mix with facts, sometimes making it difficult to know where the fiction ends and the real story begins.

Police agencies monitor the blogs in their search for clues, which experts say could muddy the process of deciding what's true, but which also sometimes generate useful information.

"There's this mystique of the detective, the Sherlock Holmes who comes in cold and figures out who done it," said Ken Novak, associate professor of criminal justice at the University of Missouri-Kansas City. "The reality is that type of investigation is exceedingly rare. Police rely on information from the public. ... Gossip and poor information is sometimes better than none."

After Jodi Sanderholm disappeared in Arkansas City, Kan., speculation about what happened to her spread rapidly across the Internet. One Arkansas City resident posted messages on Huff's blog discussing what the local police were doing to find Sanderholm, and how the community felt.

Others shared gossip and theories, information they found on the Web and secondhand news about the 19-year-old Cowley College student's disappearance.

"People feel powerless," said Huff, who lives near Atlanta. "They want to feel like they are doing something about it."

Sanderholm disappeared Jan. 5 after stopping at a Subway restaurant in Arkansas City. She had been a high school valedictorian, member of the college's dance team and considered a responsible young woman.

"This happened in a place where things don't happen like this," Huff said. "On one hand, you have a mystery; on the other, a cautionary tale. I sometimes think people need to be reminded it can happen anywhere."

Before Sanderholm's body was found and word of a suspect came out, many on Huff's blog offered their own theories, including one poster who wrote that the woman's clothes had been found.

"You get speculation, wild theories," said Kyle Smith, spokesman for the Kansas Bureau of Investigation. "Sometimes there are leaks of information you don't want out."

Smith said investigators monitored blogs and Web sites when they were looking for the BTK serial killer in Wichita, Kan., watching to see if the killer was communicating on the Internet.

"Blogs have the time and space to go into a case in great detail," said Laura James, a lawyer who has a blog called Historic True Crime. "And since so many cases now have an Internet component to them ... it's logical to look to the Web for details about certain news stories."