An Australian man was jailed for at least 10 years over a hoax bomb threat involving a teenage girl. The man attempted to extort money from the girl’s wealthy family after breaking in to their home and placing a device around the girl’s neck.

Paul Peters, a 52-year old investment banker, pleaded guilty on Tuesday over charges of aggravated breaking and entering, and detaining the teenager for advantage, AFP reports.

Peters broke into the Pulver family mansion in 2011 wearing a mask and strapped a device to 18-year old Madeleine’s neck with a note claiming it was a bomb. Police, bomb squad and other emergency services worked over 10 hours to extricate the “bomb” from Madeleine, only to find out that it was a fake explosive. He was arrested and extradited from the US in September.

According to a Sydney court, Peters was suffering psychiatric problems after his marriage failed and lost custody of his children. Peters had wandered Sydney’s suburbs to “re-live scenes” in a novel he was writing and came to believe he was John Chan, his protagonist and an “avenging character”. Prosecutors described the case as an act of “urban terrorism” fueled by financial greed.

The ruling was a “great sense of relief” for the family, Bill Pulver said.