This year Mexico will hold both its presidential and congressional election at the same time. With such high stakes, political parties are being accused of systemically using bots and cyber trolls to spread online propaganda – even though they deny this. Researchers and activists have catalogued examples of bots and troll farms being used to promote specific candidates

Presenter: Anisa Subedar

(Photo: Automated accounts boosted the 2012 presidential campaign of Enrique Pena Nieto. Credit: Getty Images)