RIVERHEAD, N.Y. (AP) — Two people were charged with murder on Monday in the killings of a couple whose remains were found scattered around Long Island earlier this year.

Jeffrey Mackey, 39, and Alexis Nieves, 33, pleaded not guilty to killing Malcolm Brown and Donna Conneely, of Yonkers, at their arraignment in state court in Riverhead.

Mackey, Nieves and two other people were previously charged with concealing a human corpse and tampering with evidence in connection with the discovery of body parts in Long Island parks in late February and early March.

Assistant Suffolk County District Attorney Frank Schroeder said in court that Mackey stabbed Brown and Conneely to death and Nieves beat one of them with a meat tenderizer following a dispute over an earlier armed robbery.

“While the case involves the cutting up of bodies of two human beings, the barbarity of those acts were only exceeded by the brutality of the murders themselves,” Schroeder said, according to Newsday.