[4] Officer Victor Avila explained that the aftermath of the shooting was "mass chaos," as numerous people rushed out of the store.
[5] Just before 6:30 p.m. MT, Thornton police tweeted there were "multiple parties down" and instructed people to avoid the area.
[6] Just before 8:00 a.m. MT, Ostrem was arrested in Westminster near 72nd Avenue and Federal Boulevard,[7] less than 10 miles (16 km) from the location of the shooting.
[14] While many shoppers were inside the store, some of them remained outside to give their condolences to the deceased, and to leave messages for the survivors.
"[17] The gunman, Scott Allen Ostrem (born August 3, 1970) of Denver, shot at people using a handgun.
[23] Ostrem unexpectedly took off from his job as a sheet metal worker at a roofing company hours prior to the incident.
[24] Ostrem's stepsister said he suffered brain damage from taking LSD almost 30 years ago and has heard voices in his head since then.
[24] Young did not comment when questioned by reporters regarding a motive for the incident and whether authorities were contemplating hate crime charges, as the three individuals killed were Latino, while Ostrem is white.
[25] District Attorney Dave Young told Denver7 on November 6, 2017, it was too soon to determine if he'd pursue the death penalty, but said he'd talk to the victims' families prior making a decision.