A late-night search of a storage unit Tuesday turned up the 9mm Walther pistol, as well as the hard drive removed from the security system of the home where police say Alan, 19, fatally shot his parents and younger sister on Oct. 9.
The tragedy preceded a weekend of partying in Dallas, according to a search warrant, reports NewsOk.com.
Also recovered from the unit: blue rubber gloves, a black Calvin Klein purse belonging to Alan’s mother Joy (known as “Tinker”), 48, as well as an iPad, an iPad Mini, jewelry, a money card, a Rolex watch, prescription medication, other medication and an Apple computer.
The recovered items suggest Alan, who confessed to police on Oct. 14 and said he hoped to be sole heir to inheritance that would allow him to pay a $3,000 debt to a loan shark, may have tried to stage the killings as a robbery. His parents had cut him off financially for his free-spending ways.
His court-appointed defense attorney, James Berry, has not spoken publicly about his client and could not be reached for comment by PEOPLE.
Investigators building a timeline were able to debunk Alan’s initial account – saying he’d tossed the weapon and equipment from the Hrubys’ home-surveillance system into a nearby lake – after they found surveillance footage that showed Alan’s 2014 black Jeep Renegade pulling into the area of the storage buildings at 7:54 p.m. Oct. 9, according to the latest court records. He then left about three and a half minutes later.
That discovery led to the search of the storage unit.
Police told PEOPLE that sometime on the night of Oct. 8 or early on the morning of Oct. 9, Alan – a political science major at the University of Oklahoma in Norman, 75 miles away – drove to Duncan and stole the pistol from the pickup of his father, John, 50. John Hruby reported the gun missing on the afternoon of Thursday, Oct. 9.
That evening, according to three murder charges filed against Alan, he was back in the family home, where he shot first his mom, then his sister Katherine, 17; and finally his dad.
The family was loved and well-known for its civic and charitable work in Duncan and nearby Marlow, where John Hruby was publisher of the weekly The Marlow Review and also The Comanche County Chronicle in Elgin.
A housekeeper found the bodies of each on the kitchen floor four days later.
Court records, along with the search warrant that was filed Wednesday, say investigators also located athletic shorts and a shirt described by the accused.
“Alan Hruby … stated that on his way to Dallas after murdering his family, he had discarded the clothing on the side of the road somewhere between Duncan and Texas but before he had entered a four-lane road,” Stephens County District Attorney investigator Justin Scott wrote.
Afterward, Alan told police, he went to Dallas, staying at the Ritz-Carlton during the weekend of the Oklahoma-Texas football game.
“He said, ‘I didn’t make it to the game,’ ” Duncan Police Chief Danny Ford tells PEOPLE, ” ‘but I went to a lot of bars.’ “
For more about Alan Hruby and the impact his murders have had on Duncan, Oklahoma, pick up this week’s issue of PEOPLE, on newsstands Friday
