Venezuelan security forces have searched the homes of two key supporters of opposition leader Juan Guaido, who is escalating a campaign to oust President Nicolas Maduro.

Venezuelan intelligence agents early Thursday entered the homes of opposition lawmaker Sergio Vergara and of Roberto Marrero, a lawyer who heads Guaido's office. Both men accompanied Guaido on a recent Latin American tour to build international support for his efforts to remove Maduro.

Guaido confirmed the operation against his aides in a Twitter post. Vergara also tweeted about security forces entering his home, saying they were violating his parliamentary immunity.

Guaido says he is the rightful leader of Venezuela and that Maduro's re-election last year was illegitimate. Maduro says Guaido is a collaborator in a U.S. plot to overthrow his government.