  The role of social media in promoting media pluralism was initially viewed as
wholly positive. However, some governments are allegedly manipulating social
media by hiring online commentators (also known as trolls) to spread propaganda
and disinformation. In particular, an alleged system of professional trolls
operating both domestically and internationally exists in Russia. In 2018,
Twitter released data on accounts identified as Russian trolls, starting a wave
of research. However, while foreign-targeted English language operations of
these trolls have received significant attention, no research has analyzed
their Russian language domestic and regional-targeted activities. We address
this gap by characterizing the Russian-language operations of Russian trolls.
We first perform a descriptive analysis, and then focus in on the trolls'
operation related to the crash of Malaysia Airlines flight MH17.
  Among other things, we find that Russian-language trolls have run 163 hashtag
campaigns (where hashtag use grows abruptly within a month). The main political
sentiments of such campaigns were praising Russia and Putin (29%), criticizing
Ukraine (26%), and criticizing the United States and Obama (9%). Further,
trolls actively reshared information with 76% of tweets being retweets or
containing a URL. Additionally, we observe periodic temporal patterns of
tweeting suggesting that trolls use automation tools. Further, we find that
trolls' information campaign on the MH17 crash was the largest in terms of
tweet count. However, around 68% of tweets posted with MH17 hashtags were
likely used simply for hashtag amplification. With these tweets excluded, about
49% of the tweets suggested to varying levels that Ukraine was responsible for
the crash, and only 13% contained disinformation and propaganda presented as
news. Interestingly, trolls promoted inconsistent alternative theories for the
crash.
