Warren, Schiff Sound Alarm on Army Plant Ammo Linked To Mass Shootings, Mexican Cartel Violence

Warren, Schiff Sound Alarm on Army Plant Ammo Linked To Mass Shootings, Mexican Cartel Violence

"The government's failure to establish processes and procedures to ensure that ammunition produced at the Lake City plant is not smuggled across the border is effectively helping arm transnational gangs abroad."

Text of Letter (PDF)

Washington, D.C. - U.S. Senators Elizabeth Warren (D-Mass.), a member of the Senate Armed Services Committee, and Adam Schiff (D-Calif.), a member of the Senate Judiciary Committee, led their colleagues in pressing Secretary of Defense Pete Hegseth and Department of Justice (DOJ) Acting Attorney General Todd Blanche on how ammunition made at the U.S. Army-owned, taxpayer-funded Lake City Army Ammunition Plant has become regularly used to perpetrate violence by dangerous Mexican cartels abroad and in shootings across the United States.

The letter is also signed by U.S. Senators Alex Padilla (D-Calif.), Tammy Duckworth (D-Ill.), and Peter Welch (D-Vt.).

"We are concerned that the ongoing lack of accountability, oversight, and transparency over commercial sales of ammunition manufactured at this taxpayer-funded facility is directly enabling assailants and transnational gangs to use these weapons to assail our communities," the senators wrote.

The U.S. Army Joint Munitions Command allows the ammunition facility's operator, Olin Winchester, LLC, to profit from the commercial sale of rounds produced at this site-including ammunition purchased by the military, some of which is powerful enough to immobilize vehicles. The lack of oversight or transparency over the commercial sales of these military-ready rounds has led mass shooters and traffickers to explicitly covet this ammunition.

Law enforcement officials have identified bullet casings originating from the Lake City plant at the sites of some of the worst mass shootings in our country's history, including San Bernardino. Aurora, Las Vegas, Buffalo, and Uvalde. This ammunition is also regularly used by dangerous Mexican cartels who smuggle in high-powered weapons and rounds from the United States in what is known as the "Iron River," with almost half of the .50 caliber cartridges seized by Mexican authorities from cartels having been linked to the Lake City plant.

"We firmly believe that the DOJ and DOD must immediately implement common-sense transparency and oversight measures, such as flagging retailers who make suspect sales of Lake City plant ammunition, to ensure that taxpayer dollars do not continue to enable mass shootings, subsidize deadly drug trafficking, and fuel cartel violence," continue the senators.

The senators are pressing for detailed responses about the commercial sale of ammunition produced at the plant, the profit generated by the contract, how many Lake City plant rounds have been used in domestic and international criminal shootings, and information about whether any processes and procedures exist to prevent ammunition from falling into the hands of international drug cartels.

Senator Warren has led efforts to implement gun violence prevention reforms and hold agencies accountable for their handling of firearms sales:

• On March 5, 2026, Senator Warren reintroduced the Stop Militarizing Our Streets Act to prohibit defense contractors and U.S. military-owned manufacturing plants from selling military-grade assault weapons and ammunition to civilians.

• On October 27, 2025, Senator Warren led 50+ members of Congress in pressing the Department of Commerce and the Department of State for answers about the elimination of a rule that was stemming the export of dangerous weapons to cartels and criminal organizations around the world.

• On October 24, 2024, Senator Warren led members of Congress in pressing the Department of Justice and Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) requesting that the ATF ramp up its work to mitigate the influx of illegal firearms from other states to Massachusetts.

• On September 27, 2024, Senator Warren led members of Congress in putting pressure on the Departments of State (State), Homeland Security (DHS), Commerce (Commerce), and Justice (DOJ), urging them to strengthen steps to prevent the flow of illegal firearms from the United States into Haiti.

• On August 7, 2024, Senator Warren led the first introduction of the Stop Militarizing Our Streets Act to stop military-grade assault weapons and ammunition from finding their way onto our streets.

• On July 15, 2024, Senators Warren, Alex Padilla (D-Calif.), and Mazie Hirono (D-Hawaii) and Representatives Jamie Raskin (D-Md.) and Robert Garcia (D-Calif.) sent a letter to the Department of Defense calling on them to stop subsidizing the sale of military-grade weapons to civilians.

• On May 15, 2024, Senator Warren and Representatives Joaquin Castro (D-Texas), Adriano Espaillat (D-N.Y.) and Ilhan Omar (D-Minn.) sent a letter to United States Trade Representative (USTR) Ambassador Katherine Tai, writing in support of USTR's decision to remove the designation of import license requirements for explosives, firearms, and ammunition as trade barriers in the annual National Trade Estimate (NTE) report, while also criticizing the Department of Commerce's inadequate steps to address assault weapons exports.

• On January 24, 2024, Senator Warren and Senator Durbin (D-Ill.), Chair of the Senate Judiciary Committee, and U.S. Representatives Castro and Norma Torres (D-Calif.) sent a letter to Secretary of Commerce Gina Raimondo, calling on the Department of Commerce to incorporate a set of recommendations from the lawmakers to strengthen export controls and end-use checks for firearm exports to crack down on the unnecessary export of lethal weapons used in brutal killings abroad.

• In December 2023, Senator Warren and Representative Dean led lawmakers in a letter to American Express, Visa, Mastercard, and Discover, requesting that they explain why their companies have paused the implementation of a new Merchant Category Code (MCC) for gun and ammunition retailers that could help flag suspicious firearm purchases and prevent gun violence, gun trafficking, and domestic terrorism.

• In December 2023, Senator Warren and Representative Hank Johnson (D-Ga.) reintroduced the Gun Violence Prevention and Community Safety Act, a comprehensive bill that would implement bold and robust measures including creating a federal gun licensing system, strengthening background checks, banning military-style assault weapons and other lethal accessories, holding the gun industry accountable for wrongdoing, and investing in research and community-based gun violence prevention.

• In November 2023, Senator Warren and Representative Maxwell Frost (D-Fla.) sent a letter to six major financial institutions calling on them to provide critical information on their efforts to end their financial investments in the gun industry.

• In September 2023, Senator Elizabeth Warren, Senate Majority Leader Chuck Schumer (D-N.Y.), and Representative Maxwell Alejandro Frost (D-Fla.) led 68 lawmakers in a letter to President Joe Biden, urging him to take further executive action to combat gun violence and limit the sale of assault weapons, including to leverage the federal government's purchasing power to improve public safety.

• In March 2023, Senators Warren and Bob Menendez (D-N.J.) sent a letter to the U.S. Department of the Treasury and the U.S. Department of Justice (DOJ), urging the departments to issue guidance to financial institutions for the full implementation of the MCC that the International Organization for Standardization (ISO) approved in 2022 for gun and ammunition stores.

• In September 2022, Senators Warren and Murphy (D-Conn.) and Representatives Castro and Torres sent a letter to Secretary Raimondo, calling out Commerce for its increased approvals of export licenses for assault weapons and high-capacity magazine exports, and for putting the gun industry profits before national security and human lives. The lawmakers called on Commerce to revise its approach to assault weapons exports and to answer questions about its export license approvals.

• In September 2022, Senator Warren and Representative Dean sent letters to the CEOs of MasterCard, American Express, and Visa urging them to support the creation of a new MCC for gun and ammunition retailers and to request information about their reported opposition to Amalgamated Bank's application for such a code.

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