Christopher Giles, 23, was familiar with the Austin couple - Gavin Free and Megan Turney - due to their YouTube fame, according to the warrant, which is based on information from the Albuquerque and Austin police departments.
Giles reportedly fired gunshots inside and outside of the house, causing police to return fire.
As police arrived on scene, a Lincoln sedan with New Mexico plates was seen backing out of the driveway to the home.
A preliminary postmortem examination by the Travis County Medical Examiner found that Giles may have shot himself, according to the affidavit, but an official ruling on his manner of death is underway. People whom police interviewed - who were not named in the warrant - described Giles as single, lonely and disturbed, the document says.
Detectives said it was clear that Giles "developed a fondness of Turney yet resented Free for his lifestyle and success".
The search warrant also revealed notes Giles wrote in his phone that provided more insight into his motives. Kotaku reports that the pair hid in a closet during the incident, from which they called the authorities.
According to newly released New Mexico court documents, it all started on January 26, when Meg and Gav were awakened at around 3:40 a.m.by the sounds of a gunshot and glass breaking. When Giles fired his gun, an officer returned fire.
When cops searched Giles' phone, they found "threatening thoughts were recorded by Giles and directed towards" Free, including "I want Gavin Free to die alone, with no children", the Albuquerque Journal reports. They said security footage shows him searching the home for the residents, a gun in his hand.
"Based upon the known circumstances and investigative findings, your affiant is led to believe that evidence related to the planned burglary and homicides of Megan Turney and Gavin Free will be found", a detective wrote in the affidavit. At least one round was sacked in the house as he searched the house.
The man, who police later discovered had driven eleven hours from Albuquerque, New Mexico, turned out to be a deranged fan of Turney, a popular vlogger and video game streamer with over 340K subscribers.
"Hey everyone. I just wanted to say thanks for all the support and concern regarding the recent incident, ' he tweeted on Monday". I want to give a huge thanks to @Austin_Police for the wonderful response time.
Meg also thanks the Austin Police "for their quick response" and "ongoing support during this hard time".