Detectives claim after killing Matulka and the dog, Barnes left the home, but returned a short time later.
"I think it was around 11.30-ish that he returned. There was just a number of things that pointed immediately to him," Stukenholtz said.
He said that vital video evidence from a surveillance camera was missing as was Barnes' truck.
At the time of his arrest, Barnes allegedly told detectives, "I wish I could have stopped myself."
On a website created for the couple's upcoming nuptials in October, photos show them appearing loved up and happy.
In one, they share a kiss, while in another they beam alongside each other into the camera.
It lists their ceremony as happening at 3.30pm which would have been followed by a wedding reception.
Kolton Barnes was arrested within 12 hours. Photo / Saunders County Sheriff's Office
Saunders County Sheriff's Office shared details of Barnes' arrest on Facebook, writing an arrest was made within 12 hours of the murder case opening and thanking those in the local community for assisting.
"We would also like to thank Deb Wilcox and the Saunders County Lost Pets-Pet Rescue staff for their assistance in locating a family cat that lived at the scene, taking care of it, and ultimately reuniting it with the 6 and 11-year-old children that not only lost their mother but a family dog that was also killed in this incident," the post read.
Local residents responded with shock, writing they were "unable to comprehend" what had happened.
