A 20-year-old man from Savage, Minnesota, is facing federal charges for illegally owning a machine gun and attempting to buy hand grenades from a law enforcement informant, according to the Department of Justice.

River William Smith, 20, was arrested on Wednesday after allegedly meeting an informant during an FBI sting to buy grenades and an illegal firearm part that would convert his AR-15-style rifle into a fully automatic machine gun, according to a press release from the DOJ.00

During the meeting, Smith allegedly tried to buy three hand grenades and four auto sears. The 20-year-old was taken into custody and charged in federal court with one count possession of a machine gun and one count of attempt to receive and possess destructive devices. 

According to court documents, the FBI was first made aware of Smith in September after a concerned citizen submitted a tip about "disturbing behavior" from the 20-year-old at a firing range.  

A retired police officer and SWAT commander who worked at the gun range tipped off law enforcement after he saw Smith wearing tactical gear and firing 300 rounds of ammunition during "rapid reload drills," according to the affidavit. 

The FBI Joint Terrorism Task Force started investigating Smith and found he was allegedly preparing for a violent exchange with police. Law enforcement discovered Smith had access to fully automatic rifles, handguns, suppressors, body armor and a Kevlar helmet, according to documents.

An informant talking to Smith at the firing range asked him about his "aggressive shooting style." Smith allegedly said he was preparing to fight the police and was "dedicated to dying in the fight," read the court documents. 

Smith explained he was anti-police after he was previously arrested by authorities who had taken away all of his firearms. 

According to the affidavit, on Dec. 31, 2019, law enforcement officers were called to Smith's residence after the then 17-year-old fired three rounds of an AK-47-style rifle inside the home. One of the bullets ultimately injured his grandmother after it traveled through a door and struck her in the other room.

Police executed a search warrant and found an AK-47-style rifle, two loaded handguns, a second rifle, a shotgun, 15 fully loaded magazines, tactical equipment, and ammunition in the home, authorities said. 

The warrant uncovered Smith's internet searches about Nazis and videos of "homosexuals being killed." His external hard drive had multiple computer files related to building bombs, homemade firearms, and schematics for creating fully automatic firearms, according to the affidavit.

While talking with informants to obtain new weapons, Smith allegedly stated he was "pro mass shooting" and sympathized with the Parkland school shooter. He also "expressed admiration" for the alleged gunman recently charged in the Colorado Springs LGBTQ nightclub shooting, which killed five people and injured 17 others.

"I think he's a hero," Smith said, according to court documents. 

The affidavit states Smith was not old enough to buy firearms, and his grandmother allegedly bought them for him. At the time of the arrest, Smith had a Glock handgun with a bullet in the chamber, two full magazines, and was wearing soft armor. 

Smith appeared in federal court on Thursday and was ordered by the judge to remain in detention at Sherburne County Jail. 

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