MIAMI, Florida (AP) -- An anti-Castro activist who earlier this year helped shelter an exiled militant linked to deadly bombings was arrested on federal weapons and false passport charges.

Santiago Alvarez was charged Saturday with possession of automatic weapons, including some with the serial numbers erased, and possession of a false passport, said Matthew Dates, a spokesman for the U.S. attorney's office in Miami. He declined to give any further detail Monday.

Alvarez's lawyer, Kendall Coffey, said his client has not broken any U.S. laws. "He's certainly an enemy of Castro but not the people of this country," Coffey, a former U.S. attorney, said Monday.

A court appearance was scheduled for Monday afternoon.

Cuba has been pressuring the U.S. government to take action against Alvarez and others who Castro claims helped smuggle militant Luis Posada Carriles into this country in March.

However, there was no immediate indication if the charges were related to Posada, who is wanted by both the Cuban and Venezuelan governments for his alleged role in the deadly 1976 bombing of a Cuban jetliner and bomb attacks in Havana in 1997-98.

Alvarez said he helped shelter Posada in Miami until federal agents arrested Posada in May on charges of entering the United States illegally. But he denied smuggling Posada into the country. Now 64, Alvarez came to the U.S. in 1959, the year Castro took power in Cuba.

In September, an immigration judge ruled that Posada could not be deported to Cuba or Venezuela because he likely would be tortured there.

Cuban exiles see Posada as a freedom fighter, while Venezuela and Cuba label him a terrorist.

Copyright 2005 The Associated Press.