Here are things to know about the shooting and the investigation:THE LATEST:Detectives on Sunday searched an apartment where 20-year-old Arcan Cetin lived in Oak Harbor, Washington. Authorities say the gunman initially entered the Cascade Mall in nearby Burlington, Washington, without a weapon shortly before 7 p.m. Friday. THE SUSPECT:Cetin immigrated to the U.S. from Turkey and went to high school in Washington state. Authorities have not disclosed a motive for the shooting and say they have ruled out nothing. Authorities on Sunday were still withholding most names of the victims pending autopsies and notification of the victims' relatives.

Source: ABC News September 25, 2016 22:18 UTC