Seven more charges, including attempted murder, have been filed against a former pizzeria manager accused of kidnapping two boys and holding one of them for four years.

Michael Devlin was already charged with kidnapping Ben Ownby, 13, in January in Franklin County and with kidnapping Shawn Hornbeck, then 11, in 2002 in Washington County.

He also was charged with several counts of forcible sodomy in St. Louis County, where Devlin allegedly kept the boys, and with federal counts of pornography and transporting a boy across state lines.

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Washington County prosecutor John Rupp filed the additional charges Monday against Devlin, accusing the 41-year-old of attempted murder, kidnapping, armed criminal action, three counts of forcible sodomy and one count of attempted forcible sodomy.

The new charges allege that Devlin tried to suffocate "SH" after kidnapping him. The papers only give the initials, which match Shawn's name.

Rupp declined to discuss details of the charges he announced Tuesday. He said the crimes occurred through early November 2002 in Washington County but would not say if Devlin was keeping Shawn in the county, instead of at his apartment in St. Louis County. Shawn disappeared in October 2002.

Michael Kielty, an attorney for Devlin, said prosecutors have not shared details of the allegations against his client.

"Again, we haven't seen any evidence," Kielty said. "We have requested it time and time again."

Shawn and Ben were found Jan. 12 at Devlin's apartment in Kirkwood. Ben had been kidnapped four days earlier after getting off a school bus near his home in the Franklin County town of Beaufort. Shawn, now 15, had been riding his bike in the Washington County town of Richwoods when he disappeared.

Investigators still are checking for potential connections between Devlin and cases in Missouri, Illinois, Minnesota and Michigan, some that date to the late 1980s. Until his arrest in January, Devlin had no criminal record.

At the news conference, Highway Patrol Sgt. Al Nothum asked anyone from the public to come forward if they have ever loaned a vehicle to Devlin.

"We know for a fact that he drove a lot of vehicles that were not his," Nothum said. He also said Devlin was known to travel widely in Lincoln and St. Charles counties.

"We categorically deny any involvement in any other cases," Kielty said. "I'm sure if they had credible evidence, somebody would have leaked it — they've leaked everything else."

While it is The Associated Press' policy not to identify alleged victims of sexual abuse in most cases, the story of Shawn and Ben has been widely publicized and their names are now well-known. Also, their families have gone public, conducting several media interviews.