Posted Monday, November 30, 2009 --- 8:45 a.m.

WEST BEND, Wis. (AP) -- A 49-year-old Theresa man arrested for a 10-year-old killing in Germantown faces a jury trial this June.

Mark Libecki pleaded not guilty last week to first-degree intentional homicide for the May 1999 stabbing of his co-worker, Theresa Wesolowski. Another co-worker at the box factory where they worked found the 22-year-old Wesolowski's body near the plant with 46 stab wounds.

Investigators obtained a DNA sample from Libecki at the time. In 2006, analysts at the state crime lab matched it to DNA lifted from Wesolowski's hands. And last summer, investigators searched a Ford Explorer once owned by Libecki and found a blood sample with DNA that matched the victim.

Washington County District Attorney Todd Martens tells The Reporter in Fond du Lac that it's the most brutal and vicious crime he's worked on in 18 years as a prosecutor.

Copyright 2009 by The Associated Press. All Rights Reserved.