The federal agents arrested an agitated and heavily armed Colorado man for saying that he was surprised that his friends did not suspect him as the shooter in the "Boulder massacre."

Based on the court documents released on Friday, an Iowa gun store also refused to sell a semi-automatic rifle to Adam Vannoy, 40, after he said that remark.

Reports said the Nebraska State Patrol initially arrested Vannoy on Mar. 14 along Interstate 80 in Lancaster County. A driver has called the police to report the self-described firearms enthusiast was driving recklessly at speed around 120 mph. 

Firearms Seized on Adam Vannoy

While searching his truck during the initial arrest, troopers seized a handgun from Vannoy's jacket. A loaded AR-style semi-automatic rifle with an illegal silencer, four other firearms, ammunition, a bulletproof blanket, a bulletproof vest, an Air Force costume, two brown wigs, and marijuana were also found in Vannoy's possession.

According to Fox News, the federal complaint stated that the Colorado man threatened to kill a guard during his initial arrest. He also exposed his penis to the officers on duty and threw feces from his cell into a common area.

But after facing charges of weapons and drugs, the Colorado man was able to bail himself out after he posted a $5,000 bond on Mar. 17.

On Tuesday, six days later after his release, Adam Vannoy asked for an AR-style rifle from Sportsman's Warehouse in Ankeny, Iowa, which is near Des Moines.

But the store denied the sale after the suspect mentioned that he was surprised that his friends had not called to find out if he was responsible for the "Boulder massacre," wherein a 21-year-old man is charged for killing 10 individuals at a grocery store.

The Colorado man also said that he had 500 rounds of ammunition in his truck. The firearms store did not only refused the purchase, but it also notified the Bureau of Alcohol, Tobacco, Firearms, and Explosives regarding his "Boulder massacre" comment.

Federal agents arrested Vannoy in Iowa this week on a new federal charge stemming from the Nebraska traffic stop, an unlawful user of marijuana, and illegal possession of a firearm.

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On Friday afternoon, Vannoy made an initial court appearance in front of U.S. Magistrate Judge Stephen Jackson, who ordered the temporary detention of the Colorado man due to pending further proceedings, which includes a potential transfer to face the charge in Nebraska. 

Jackson also ruled that Adam Vannoy was qualified financially to be represented by a lawyer at federal taxpayer expense, The Associated Press reported.

Meanwhile, Vannoy also posted in his Instagram account a video that includes a receipt on his purchase at Brownells, which is a large firearms and accessories retailer in Grinnell, Iowa, after his release from Nebraska custody, where he purchased close to $3,000 in merchandise. 

He also mentioned in the videos that the best way to show the Nebraska State Patrol that he was not plotting anything heinous was to rearm himself, CBS Denver reported.

While not disclosing customer order details, Brownells spokesman said Friday that their company did not sell any firearms to Vannoy.

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