WILMINGTON -- A serial rapist who terrorized women around Greenfield Lake will spend at least eight years behind bars. Shawn Green learned his sentence Thursday in New Hanover County court. Prosecutors say Green raped three women in 2005. Thursday he pleaded down from first-degree charges to second-degree charges. Investigators say 28-year-old Shawn Keith Green picked up two prostitutes in the Greenfield Street area in 2005. He then assaulted and forced the women to have sex. Prosecutors say Green was giving the third victim, a stranger, a ride when he assaulted her and forced her to have sex. It took investigators six months to arrest Green. He was originally charged with three counts of first-degree sex offense and two counts of first-degree rape. Green will spend at least eight years behind bars. He will also become a registered sex offender. Witnesses in court Thursday say Green turned to one of the victims and apologized.