Missouri detectives investigating accused kidnapper Michael Devlin have shown photographs to relatives of a child missing since 1991 that came from someone who claims to know the former pizzeria worker.

The person who claims to know Devlin told police they thought the boy pictured in the photos was an acquaintance of Devlin's from years ago, said James McWilliams, the uncle of Charles "Arlin" Henderson, who disappeared in July 1991 at the age of 11 while riding his bike on a rural road in Moscow Mills, about an hour's drive north of St. Louis.

Lincoln County detectives are part of a state and federal task force investigating Devlin to see if he is linked to other child abductions.

The detectives showed Henderson's relatives the photos this week. Family members said they look like they could be of the long-lost boy.

Devlin, 41, is charged with kidnapping Shawn Hornbeck and Ben Ownby in similarly remote areas. Shawn, now 15, and Ben, 13, were found Jan. 12 at Devlin's suburban St. Louis apartment. Authorities are investigating whether he could be linked to Arlin's disappearance.

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Lincoln County Sheriff Department Lt. Rick Harrell did not return phone messages seeking comment. He said last week the department would not comment on the Henderson investigation.

The photos are roughly 10 years old and show a teenager of about 17, the relatives said. Arlin would have been 17 in 1997.

The teenager looked like he could be her son, Debra Henderson said.

"Yeah, he really did," she said. "But I am not getting my hopes up."

McWilliams said there was a "strong, strong" resemblance to Arlin, but he couldn't say for sure if it was him.

"There are some characteristics there that are the same. We're keeping an open mind," McWilliams said.

Detectives were investigating whether the source did in fact know Devlin, McWilliams told The Associated Press.

Debra Henderson told FOX News she has yet to hear back from detectives about the recent photos, and said she appreciates fact her son's disappearance is back in the public eye after so many years have gone by.

Devlin is being held in lieu of $1 million bail and faces two counts of kidnapping and one count of armed criminal action.

Lincoln County detective Chris Bartlett said this month that Devlin became the "most viable lead" in the Henderson case after his arrest. Detectives cited the fact that all three abductions happened in remote areas, all about the same distance from Devlin's home. All three boys were about the same size.

But the St. Louis Post-Dispatch, citing sources "familiar with the investigation," reported that authorities believe that two photographs provided by the woman are not a credible lead in the investigation of Arlin's disappearance.

Click here to read the Post-Dispatch story

The woman claiming to know Devlin gave the photos of Arlin to the newspaper over the weekend, saying they showed a teenage boy she met through Devlin in the mid-1990s. She said Devlin identified the boy as the son of one of his friends. Devlin himself is not in the photos.

The Associated Press contributed to this report.