  Coordinated multi-platform information operations are implemented in a
variety of contexts on social media, including state-run disinformation
campaigns, marketing strategies, and social activism. Characterized by the
promotion of messages via multi-platform coordination, in which multiple user
accounts, within a short time, post content advancing a shared informational
agenda on multiple platforms, they contribute to an already confusing and
manipulated information ecosystem. To make things worse, reliable datasets that
contain ground truth information about such operations are virtually
nonexistent. This paper presents a multi-modal approach that identifies the
social media messages potentially engaged in a coordinated information campaign
across multiple platforms. Our approach incorporates textual content, temporal
information and the underlying network of user and messages posted to identify
groups of messages with unusual coordination patterns across multiple social
media platforms. We apply our approach to content posted on four platforms
related to the Syrian Civil Defence organization known as the White Helmets:
Twitter, Facebook, Reddit, and YouTube. Results show that our approach
identifies social media posts that link to news YouTube channels with similar
factuality score, which is often an indication of coordinated operations.
