Arapahoe man gets 5 years in federal prison after Riverton gunfire

CHEYENNE, Wyo. - Aaron Michael Underwood, 40, of Arapahoe, Wyoming, was sentenced to 60 months in federal prison, followed by three years of supervised release, for being a felon in possession of a firearm. U.S. District Court Judge Alan B. Johnson imposed the sentence on Oct. 13, 2026.

According to court documents, the Bureau of Indian Affairs responded on March 22, 2026, to a 911 call reporting a disturbance and shots fired in Riverton. Active gunfire was audible on the emergency dispatch call. Responding officers learned that an earlier family argument escalated when Underwood, who resided in an adjacent modular home on the property, discharged a firearm. Witnesses also documented a pattern of ongoing threats and prior firearm brandishing.

When law enforcement arrived, officers found the modular home door barricaded from the inside before detaining Underwood. An FBI special agent subsequently obtained and executed a search warrant, recovering a 9mm Beretta handgun and a 9mm Hi-Point/Beemiller carbine. While secured in a patrol vehicle, Underwood directed verbal intimidation toward witnesses.

The case was investigated by the Bureau of Indian Affairs, the Federal Bureau of Investigation, the Wyoming Division of Criminal Investigation, the Wyoming Highway Patrol and the Fremont County Sheriff's Office. Assistant U.S. Attorney Jesse Naiman prosecuted the crime.

Case No. 26-CR-00049.

This case was part of Project Safe Neighborhoods (PSN), a collaborative initiative uniting federal, state, local, and Tribal law enforcement with community leaders to combat gun violence and gang activity.

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