President-elect Donald Trump gave Venezuelan President Nicolas Maduro a stern warning on Thursday not to harm his country’s opposition leader.

Edmundo González has become a beacon of hope for millions of Venezuelans. They want to call him president. He believes he won that office at the ballot box last year.

Venezuela’s opposition said its banned leader María Corina Machado was detained after she emerged from hiding to join thousands of Venezuelans protesting against Nicolás Maduro’s planned inauguration after what they say is a fraudulent reelection.