(AP) — Authorities in Omaha have launched a task force to investigate any connection between last week’s killings of a Creighton University professor and his wife and the 2008 slayings of an 11-year boy and his family housekeeper.

Omaha Police Chief Todd Schmaderer said Monday that the public should report any suspicious activity as authorities investigate the deaths of Dr. Roger Brumback and his wife, Mary, as well as the unsolved 2008 stabbings of Thomas Hunter and 57-year-old Shirlee Sherman.

The Brumbacks were found slain May 14 in their Omaha home. Schmaderer has refused to say how they were killed.

Roger Brumback was a pathology professor and colleague of Thomas Hunter’s parents, who both work at Creighton. Schmaderer will only say authorities are “exploring very hard” the possibility the killings are related.