Sioux City Man Sentenced to More Than 12 Years in Federal Prison for Illegal Possession of Firearms

Angel Castillo-Martinez, age 26, from Sioux City, was sentenced August 19, 2026, to more than 12 years in federal prison, after a March 18, 2026, guilty plea to possession of a firearm by a felon.

Evidence in the case revealed, on June 5, 2025, Castillo-Martinez obtained a ride from Winnebago, Nebraska to Sioux City, Iowa with the intent to "hurt a lot of people." He was armed with a loaded handgun and a loaded rifle. Sioux City police officers saw Castillo-Martinez getting in and out of the vehicle abruptly and noticed that the vehicle was being driven by a person with a suspended license. A traffic stop ensued.

Castillo-Martinez fled on foot from the traffic stop, running through a residential neighborhood, but was quickly apprehended by Sioux City police officers. Castillo-Martinez provided officers with a false name and date of birth. Officers retraced the path of flight and found Castillo-Martinez had attempted to hide a baggie containing more the 50 grams of methamphetamine. Officers conducted a search of the vehicle and located a backpack on the passenger floorboard containing a loaded pistol as well as a second backpack containing a loaded AR-style rifle, with an obliterated serial number, in the truck bed. Following his arrest, Castillo-Martinez admitted that he was on his way to "hurt a lot of people" to seek revenge for an attack that happened to a friend two days prior. He later learned that the people he had targeted were innocent.

Castillo-Martinez's criminal history includes theft, possession of controlled substances, carrying a dangerous weapon, assault on a peace officer, and interference with official acts.

Castillo-Martinez was sentenced in Sioux City by United States District Court Judge Leonard T. Strand to 151 months' imprisonment. He must also serve a 3-year term of supervised release after the prison term. There is no parole in the federal system.

Castillo-Martinez is being held in the United States Marshal's custody until he can be transported to a federal prison.

The case was investigated by the Sioux City, Iowa Police Department and the United States Department of Justice's Bureau of Alcohol Tobacco Firearms and Explosives (ATF). This case is being prosecuted by Assistant United States Attorney Forde Fairchild

Court file information at https://ecf.iand.uscourts.gov/cgi-bin/login.plLinks to other government and non-government sites will typically appear with the "external link" icon to indicate that you are leaving the Department of Justice website when you click the link..

The case file number is 25-4035.

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