CARACAS, Venezuela (AP) — Venezuelan opposition leader Juan Guaido shrouded the route and timing of his return in secrecy amid concerns he might be detained. Yet he breezed through airport immigration checks and brazenly called for the downfall of President Nicolas Maduro at a rally where the presence of security forces was minimal.

Guaido's homecoming Monday was the latest chapter in his struggle with Maduro, who has been warned by the U.S. and others not to move against his adversary and possibly realized arresting his foe could generate more street protests.

And, while Guaido's presence is likely to add at least short-term momentum to his campaign for political change, Maduro has proven resilient and still commands the critical loyalty of top military officers.

Some analysts speculate the two sides may be considering negotiations.