A 20-year-old man has pleaded not guilty to murder charges in the shooting deaths of his parents and teenage sister at their home in Oklahoma.

Alan Hruby entered the plea Thursday in Stephens County District Court. His trial on three counts of first-degree murder is scheduled for April.

Prosecutors say they will seek the death penalty. Hruby said in a June letter to The Oklahoman that he deserves to be executed.

Hruby is charged in the October shooting deaths of 50-year-old John Hruby; 48-year-old Joy Hruby; and 17-year-old Katherine Hruby at their home in Duncan, 80 miles south of Oklahoma City. John Hruby was the publisher of The Marlow Review.

Police say Hruby killed his family so he could inherit their estate, after his parents cut him off.