BISMARCK, N.D. (AP) – The trial for a man accused of killing four people at a North Dakota property management company has been pushed back six months after attorneys requested more time to review evidence and prepare for the case.

The trial for Chad Isaak will begin Sept 14. in Morton County. The 45-year-old chiropractor is charged with four counts of murder in the deaths of RJR co-owner Robert Fakler and employees Adam Fuehrer and Bill and Lois Cobb, who were married. The four were found shot and stabbed April 1 at the Mandan business.

A motive is unknown.