He says he witnessed Holmes at an Aurora Gander Mountain a few weeks ago buying or modifying the AR-15 assault rifle, one of the types of guns Holmes is accused of using in the shooting.
Denver resident Austin McKee says Holmes had pink hair on July 1 when he saw him at that Gander Mountain. He says he was having a scope installed on it.
McKee says he was at an Aurora Gander Mountain before a hunting trip. He specifically remembers one of the other customers at the store.
"A young guy about my age walked in with pink hair and earrings," McKee said. "[He] looked a little out of place you could say."
There isn't a lot of pink haired hunters who show up at the store, according to McKee.
"He had bleached it, and it was dyed pink. It was more like a cotton candy color," he said.
CNN has been citing a law enforcement source as saying when Holmes was detained Friday, he had red hair and told the police he was the Joker.
"I called the police this morning and let them know... where he bought the gun," McKee said.
9NEWS looked at McKee's bank record to confirm the purchase of the stand.
"When he walked in there, he just looked like his eyes were super wide open," McKee said. "[He] kind of looked like silver dollars. He was out of it I could tell, obviously this isn't something a sane person would do."
McKee says the man he thinks was Holmes didn't say a word as a scope was installed on the gun.
"The gun he was looking at was an AR15, which is an assault rifle," he said. "I just had a weird feeling that that guy shouldn't be buying that type of gun. He just had a weird aura about him."
McKee says the whole experience was odd back then, and has taken even more of a bizarre twist now.
"You're sitting next to a guy who three weeks later, basically goes berserk," he said. "It's pretty unbelievable."
9NEWS asked a Gander Mountain spokesperson to confirm whether Holmes bought the AR15, or had a scope installed, at the Aurora store. They said they are not commenting on the case and that the appropriate records and surveillance video have been given to investigators.
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