A demonstrator holds a sign that reads in Spanish &quot;I want to go home today,&quot; during a protest for missing activist Santiago Maldonado, at Plaza de Mayo in Buenos Aires, Argentina, Friday, Sept. 1, 2017. Human rights groups say Maldonado went missing a month ago today, after Argentine border police captured him during an operation against Mapuche Indians who were blocking a highway in Argentina's Patagonia. (AP Photo/Natacha Pisarenko)