A bullet had earlier grazed the left side of the head of one person holding down Loughner, Audetat said. Right behind him was a woman who was also a gunshot victim.
Audetat searched Loughner.
"In his left front pocket, I found two magazines which I immediately observed to be for a Glock," Audetat said. "I was not sure of the caliber at that point, but they were Glock magazines and they were both fully loaded."
Audetat also found a foldable knife with a 4-inch blade in Loughner's front pocket.
Loughner said he was feeling hot, so the deputy removed Loughner's beanie and hooded sweatshirt.
Audetat found Loughner wearing earplugs, and Loughner also stated several times that he pleaded the Fifth Amendment, documents said.
"At that point, he said, 'I just want you to know that I'm the only person that knew about this,'" Audetat said. "That was the only thing, pretty much, that he said to me almost all day."