IOWA CITY, Iowa (AP) — Court records show an Iowa gun store refused to sell a semi-automatic rifle to a heavily armed and agitated Colorado man who said he was surprised his friends didn’t suspect he was the Boulder mass shooter. Federal agents say Adam Vannoy made the remark Tuesday when he was trying to purchase an AR-style rifle from Sportsman’s Warehouse in Ankeny, Iowa.

The store denied the sale and notified federal authorities. Vannoy allegedly said he had 500 rounds of ammunition in his truck. He has been arrested on a federal weapons charge stemming from a March 14 traffic stop in Nebraska, when authorities say he had several firearms, an illegal silencer and marijuana.