DALLAS (AP) – A federal grand jury has indicted three Texas men whom federal officials say have been linked to a gun used in a U.S. agent’s death in Mexico.

The grand jury returned a six-count indictment Wednesday against Ranferi Osorio, his brother Otilio Osorio and their neighbor Kelvin Leon Morrison. Each is charged with a single count of conspiracy and four counts of using false statements to a dealer to acquire a firearm. The Osorio brothers also are charged with single counts of possessing a firearm with an obliterated serial number.

The firearms charges aren’t directly related to last month’s death of U.S. Immigration and Customs Enforcement agent Jaime Zapata in Mexico. Mexican authorities have arrested at least two Zetas members in the agent’s shooting death. All three remain in custody.

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