AUGUSTA -- A Waterville man originally from Rhode Island will spend eight years in prison for sexually abusing two young girls who were sisters.

Olin D. Stevens, 36, pleaded guilty on Friday in Kennebec County Superior Court to three counts of unlawful sexual contact. The girls were between the ages of 12 and 14 at the time the abuse occurred, Deputy District Attorney Alan Kelley said.

He said the abuse occurred over a period of several months and ended with Stevens' arrest in November 2007.

The girls and their mother are now living in another state, Kelley said.

Kelley said the state was dropping three charges of gross sexual assault against Stevens in exchange for his guilty plea.

"The victims are very young and have emotional and behavioral problems," he said. "They would have had a great deal of difficulty in making it through a trial."

Stevens admitted his guilt to police, Kelley said. Justice Joseph Jabar sentenced Stevens to eight years in prison followed by four years of probation.

If Stevens violates probation, he can serve five more years in prison.

Kelley said Stevens had a prior conviction for a sex offense out of state.

A number of people were sentenced in separate cases heard this week in Kennebec County Superior Court:

* Thomas B. Tozier, 21, of Winslow, reckless conduct with a dangerous weapon Nov. 18, 2005, in Albion; 60 days in jail.

* Jamie B. Mondragon, 27, of Lewiston, aggravated assault, assault and criminal mischief Nov. 3, 2007, in Monmouth; five years in prison, all but 11 months suspended, three years' probation and $300 fine.

* Michael I. Fitzsimmons, 26, of Waterville, criminal mischief and terrorizing Jan. 13 in Waterville; 364 days in jail, all but 60 days, one year of administrative release; $385 restitution.

* Nelson D. Reynolds, 52, of Winslow, unlawful furnishing of marijuana and two counts of possession of scheduled drugs Oct. 10, 2007, in Winslow; six months in jail, $1,200 in fines.

* Angelo Licata, 30, of Oakland, reckless conduct Nov. 28, 2007, in Pittston.

* Joseph A. Johnson, 18, of Oakland, unauthorized use of property, burglary of a motor vehicle and theft Feb. 3 in Oakland; 180 days in jail, all but 15 days suspended, one year of administrative release.

* Rodney Skipper, 38, of Bowdoinham, disorderly conduct Jan. 8 in Augusta; $500 fine.