MESA, Ariz. – The Mesa man who confirms he sold 600 rounds of tracer ammunition to the Las Vegas shooting suspect says he never noticed anything suspicious about Stephen Paddock.

“The guy appears normal as your grandfather,” said the ammo seller, who chose to remain anonymous.

In an exclusive interview with 12 News, the seller said he first noticed Paddock at a gun show in Las Vegas in late August.

The seller would again see the 64-year-old suspect weeks later at the Crossroads of the West Gun Show in Phoenix, at the Arizona State Fairgrounds.

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The anonymous man says Paddock asked him for a specific type of ammo that he did not have at the moment. It was days later both men would meet again at the seller’s Mesa home. The transaction was made and 600 rounds of tracer bullets were sold to Paddock.

Experts say tracer rounds contain phosphorous, which ignites with heat generated as the bullet leaves the barrel. They are legal to sell.

The anonymous Mesa seller says Paddock said he was going to the desert with his friends to make a light show, and insists Paddock never looked suspicious.

“He looked normal, acted normal, spoke normal, clean cut, easy going, nice guy," the seller said. "[I] never suspected anything. Nobody around us suspected anything."

The bullets sold by the Mesa man to Paddock were found in Paddock's hotel room, according to law enforcement officials, but it does not appear they were used in the shooting.