Agents from the Bureau of Alcohol, Tobacco, Firearms and Explosives have arrested three Mexican citizens they said had guns, ammunition, drugs and more than $600,000 in cash, authorities announced Monday.

Luis Estrada, 28, Miguel Cantu, 21, and Gabriel Juarez, 53, face federal charges of illegal possession of firearms and ammunition, authorities said.

It's illegal for undocumented immigrants to possess guns and ammunition. Cantu and Estrada were in the United States illegally. Juarez had a border crosser card that authorized him to be in the country but did not permit him to possess weapons, bureau spokeswoman Franceska Perot said in a statement.

The men were arrested Saturday by San Juan police and ATF agents who found them with six guns, 2,000 rounds of ammunition, $640,000 in cash and a small amount of cocaine.

They are in the custody of U.S. Marshals. No bond hearing has been set and the men do not have attorneys yet, Perot said.

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