In this Intelligence Report: How the case began in Illinois and wound a trail overseas and back to Indiana.
FBI agents had no idea that the man on the other end of an undercover child porn deal was a former FBI agent himself. And not just any agent. Their suspect had been one of the bureau's top explosive experts. And, according to his resume, he held a law degree from DePaul University in Chicago and obtained his undergraduate degree from Northwestern.
FBI agents from Indianapolis went to the home of a retired colleague with an warrant for his arrest.
Donald John Sachtleben, 54, was charged with possessing and distributing child pornography after authorities say they found nearly three dozen illegal photos and video files.
Before leaving the FBI in late 2008, Sachtleben was in s small cadre of go-to bomb experts at the FBI. According to several sources, he managed investigative teams on Sept. 11, after the attack on the Oklahoma City federal building and bombing, and he was the lead agent on the search of the Unabomber's cabin in Montana.
The I-Team has learned that the trail to the former FBI agent began in Roscoe, Illinois, a quiet village northwest of Chicago near Rockford.
According to an FBI affidavit, last January, child pornography suspect Jason Nicoson began cooperating with authorities, allowing his Internet accounts to be used by FBI agents tracing child porn distributors and buyers.
"Nicoson states that he likes girls age 6 to 12," the affidavit reveals "in conversations dating back to 9/4/2011, Nicoson appears to be negotiating a price to pay to have webcam show put on for him by children."
In a porn deal routed through Germany, prosecutors have now charged Sachtleben as the buyer.
The retired FBI agent is in federal custody awaiting a Thursday court hearing. He has entered a preliminary plea of not guilty.
Federal prosecutors in Indianapolis say most of the images retrieved from the Sachtleben's computer were of girls younger than 11.