DALLAS (AP) - Federal investigators say the gun used to kill a U.S. immigration agent in Mexico has been traced to a Dallas-area man.

Agents of the U.S. Bureau of Alcohol, Tobacco, Firearms and Explosives arrested the man and two other suspected gun smugglers in Monday raids in a Dallas suburb.

ATF spokesman Tom Crowley is referring questions about further details to the U.S. Justice Department in Washington, D.C. He referred other questions to the Justice Department, but a department spokeswoman said no statement was planned for Monday.

U.S. Immigration and Customs Enforcement Agent Jaime Zapata was killed in the Feb. 15 attack at a roadblock in the central Mexican state of San Luis Potosi. Agent Victor Avila was wounded.

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