BEXAR COUNTY, Texas – A USAF major was arrested Sunday in connection to his wife’s disappearance after police said they found an ax, shovel, heavy duty trash bags and two five-gallon jugs of gasoline inside their Texas home.

Authorities said they believe Andre McDonald, 40, purchased the items – and destroyed the receipt – with the intent of disposing of the body of his 29-year-old wife, Andreen Nicole McDonald, who went missing Friday.

“We found some things really quite disturbing (at the residence),” Bexar County Sheriff Javier Salazar told reporters Sunday, according to mySanAntonio.com. “The evidence consisted of a shovel, an ax, some heavy duty trash bags, some work gloves, and two 5-gallon containers of gasoline.”

He said they also found a portable burn barrel and a torn up receipt, which showed the items had been purchased earlier Saturday.

“There was quite a bit of effort that went into destroying that receipt to try to prevent us seeing where it was purchased and when it was purchased,” Salazar said.

Andre McDonald, an Air Force cyberwarfare specialist with a background in engineering, was taken into custody by authorities Saturday night after they feared he might kill himself after he attempted to purchase a gun Saturday.

Salazar said the USAF officer left the store in a hurry and left the weapon and his identification behind.

“At that point, we were not certain if there were some suicidal thoughts going through the subject’s mind,” Salazar said Saturday, according to KSAT. “(Deputies) made contact with him outside the residence, took him into custody, detained him at that point due to a possible mental health issue.”

On Sunday, Salazar told reporters that Andre McDonald seemed of “pretty sound mind” and that it appeared like he was treating the investigation like a game. Consequently, he was charged with tampering with evidence.

“He’s a highly intelligent person, and I think he knows exactly what he’s doing,” Salazar said, according to KSAT. “I think that quite frankly, he probably thinks he’s smarter than anybody in law enforcement, but he’s behind bars right now.”

Meanwhile, Andreen McDonald, a business owner in San Antonio, was reported missing Friday by friends who said she never showed up at work or to the gym.

Salazar said the case has “very suspicious circumstances,” adding that the woman’s husband declined to speak with deputies when initially questioned on Friday.

“We don’t believe that Andreen McDonald is no longer living,” Salazar added.

The couple’s 6-year-old daughter is being taken care of by a relative, Salazar said.