OMAHA, Neb. — An Omaha police detective says he believes an 11-year-old boy found stabbed to death in his affluent Omaha home in 2008 was killed before the family’s housekeeper.

The Omaha World-Herald says ( ) that testimony came Tuesday in the trial of 42-year-old former doctor Anthony Garcia, charged with first-degree murder in those deaths and the 2013 killings of a Creighton University School of Medicine doctor and his wife.

Prosecutors intend to show that Garcia killed the boy, who was the son of Creighton’s Dr. William Hunter, and 57-year-old Shirlee Sherman, then five years later killed Dr. Roger Brumback and his wife, Mary. They say he was motivated by rage from being fired by the doctors from the medical school’s residency program in 2001.

Garcia’s trial is expected to last up to six weeks.

Information from: Omaha World-Herald,