describe the harrowing Aug. 3 incident, which began when a man broke into Madeline Pulver's bedroom wearing a striped balaclava and wielding a black aluminum baseball bat. He told her to sit down and chained a black box around her neck.

He also draped a purple lanyard over the terrified girl with a note saying that the black box was a bomb. The note included ransom instructions for Pulver's family, telling them to e-mail a Google address -- dirkstraun1840@gmail.com -- for further instructions. Also on the lanyard was a 4GB USB stick that contained a digital version of the note, saved as a pdf file.

The next 10 hours were a gruelling ordeal for the girl before a Sydney police bomb squad was able to determined that the threat was a hoax. But a closer look at the USB drive turned up a couple of files that the criminal thought he'd deleted. One of them, a version of the ransom note written in Microsoft Word, contained metadata about the document's author, including his name: "Paul P."

On Monday, U.S. authorities arrested Paul "Doug" Peters, 50, in La Grange, Kentucky, seeking to extradite him to Australia to face kidnapping and breaking-and-entering charges. It's not clear why Peters attempted such a bizarre crime, but U.S. prosecutors say he once worked for a company linked to Pulver's family. The girl's father, Bill Pulver, is the CEO of voice recognition software company Appen Butler Hill.

Police collected footage from surveillance cameras in a library where a computer was used to access the Gmail account. The footage, along with the USB drive and circumstantial evidence, such as purchases made around the time of the incident, link Peters to the crime, prosecutors say.