A graduate of a New England prep school who was convicted of sexually assaulting a younger student was taken into custody Friday after acknowledging that he violated conditions of his bail agreement by missing curfew.

A judge in Merrimack County Superior Court said Owen Labrie would begin his one-year jail sentence immediately.

Labrie had been living with his mother in Tunbridge, Vermont, as he appealed his sentence and the requirement that he register as a sex offender. He was supposed to be home between 5 p.m. and 8 a.m. each night, but a prosecutor said he violated it at least eight times.

In court papers, prosecutor Catherine Ruffle said that on or about Feb. 29, a journalist spoke with the 20-year-old Labrie on a train in Cambridge, Massachusetts. That prompted an investigation into Labrie's travels.

In court Friday, a lawyer for the 20-year-old Labrie acknowledged that his client "tried, admittedly, to fly under the radar on three occasions." He said Labrie was sorry.

Labrie was arrested in 2014 days after graduating from St. Paul's School, an elite prep school in Concord.

Labrie was 18 at the time of the encounter in a near-deserted building on the St. Paul's campus. Prosecutors linked the assault to a competition at St. Paul's known as the "Senior Salute" in which seniors seek to have sex with underclassmen.

A jury in August convicted Labrie of misdemeanor sex assault charges and a felony charge of using a computer to lure an underage student for sex. The computer charge, a felony, carries the mandate to register as a sex offender for life.