GOLDEN, Colo. -- A 54-year-old Nederland man was sentenced last week to six years to life for sexually assaulting his friends' sons, the Jefferson County District Attorney's Office announced Monday.

John Arthur Lovelace was sentenced on Friday after pleading guilty to sexual assault on a child in July.

Pam Russell, a spokeswoman for the Jeffco DA, said Lovelace was at the home of friends in September and October 2008 when he sexually assaulted the couple's 11-year-old son. He offered the boy crack cocaine before he sexually assaulted him and gave the boy $300 on the condition that he not tell anyone what had happened, Russell said.

During the course of the investigation involving the 11-year-old, an investigator discovered that Lovelace had also sexually assaulted the 12-year-old son of a friend in Boulder in 2001 or 2002.

In the Boulder case, Lovelace had befriended the boy's mother, and one night, when Lovelace was alone with the boy, he provided the boy with marijuana and sexually assaulted him, prosecutors said.

He also paid the boy $100 not to tell anyone, and sexually assaulted him one more time, according to the district attorney.

Lovelace agreed to a plea deal and pleaded guilty to one count of sexual assault that named both victims.

Judge Jack Berryhill said that Lovelace had used his position as a family friend for his personal sexual gratification at the expense of two young boys who were not in position to fend for themselves.

A sex offender evaluation completed on Lovelace before his sentencing found him to be at high risk to reoffend.

Berryhill sentenced Lovelace to prison for a period from six years to life, to be followed by parole from 10 years to life. When he paroles from prison, he must register as a sex offender.