While there has been extensive study about online harassment and disinformation campaigns, little research has focused specifically on the cross-platform aspect of these actions. Understanding how information operations travel across platforms, however, is central to comprehend the reach of these campaigns and develop comprehensive policy solutions. This project aims at extending our understanding about cross-platforms information operations using harassment campaigns against Brazilian journalists as a case study. For that, we employ original methods combining open source research techniques, social media analysis, lexical analysis, and interviews with victims to map tactics and narratives used in cross-platform information operations. Our main objects will be YouTube and Twitter persisting harassment against journalists in the country, complemented by the monitoring of encrypted messaging apps such as WhatsApp and Telegram. We focus on persecution of journalists because of the media´s role as government watchdogs, and on Brazil because of the deep penetration of social media platforms and applications.