Toby Studabaker, 31, was arrested in Frankfurt after disappearing five days earlier with Shevaun Pennington, sparking an international manhunt.

The two apparently met over the Internet.

Michigan State Police did not list Studabaker's name on its Public Sex Offender Registry, indicating no criminal record for sexual abuse.

"I hope they both can get home safely," Studabaker's sister-in-law Sherry Studabaker told AFP by telephone from her home in Three Rivers, Michigan. She refused further comment.

The Federal Bureau of Investigation office in Detroit told AFP it was conducting an investigation into the case.

Studabaker studied religion at the Rosedale Baptist College in Irwin, in the Midwestern US state of Ohio 1992-1993, according to the academic dean.

"He was only here for six weeks," Jon Showalter told AFP by telephone.

"There are few people who know him at all."

Rosedale is an evangelical junior Bible college in the Mennonite-Anabaptist tradition.

Studabaker's arrest came after police sources revealed that child pornography had been downloaded from the Internet onto a computer used by the former soldier. The information had previously been withheld so as not to jeopardise the investigation, the sources said.

Police also revealed for the first time that they had evidence that Studabaker was aware of Shevaun's real age, despite his claims in calls to his family in the United States that he had thought she was 19.

Studabaker has been described as a devout Christian who attended a bible college in Ohio from 1993 to 1994. His wife Jenny died of cancer last year. The couple were childless, according to family.

Studabaker grew up in Constantine, Michigan, where he trained in martial arts and was a keen player of American football. He served with the marines in Afghanistan, for which he was decorated, but left the armed services in June with a shoulder injury.

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