最近TwitterとFacebookは、過激派コンテンツ投稿との戦いを強化することを表明した。
実際、過激派による主要ソーシャルメディアプラットフォームの占有に対する、一定の戦術 ― 例えばTwitterによる重複アカウントの停止 ― が、過激派宣伝活動に影響を与えているという証拠もある。
今月Twitterは、「暴力的過激主義」との戦いを強化するために、問題コンテンツに関する報告のレビューチームを増員し、「脅迫あるいはテロ行為を推進する、主としてISISに関連する」アカウントを、2015年中期以降だけで12万5000件以上削除したことをブログで発表した。
しかし、ISISを主要プラットフォームから追放しようとするこの積極的行動がISIS支援グループの目に止まり、彼らはTwitter CEOのJack DorseyおよびFacebook CEOのMark Zuckerbergを名指しで脅迫するビデオを投稿し、2人の顔写真に弾痕を残した。
ビデオは、ウェブの詳細な分析を行うハイブリッドメディア、Vocativが発見し、ビデオのスクリーンショットを2枚掲載した。TechCrunchもそのビデオをネットで入手し、脅迫文が含まれていることを確認した。
ビデオの大部分は、ビデオを作成したISIS支援グループによってハックされたと見られる、一連のFacebookおよびTwitterアカウントを映し出しており、グループは自らを「カリフ軍の息子たち」と呼んでいる。
ビデオには他に英語で書かれたメッセージがあり、アカウント削除に直接言及している：「お前たちは毎日われわれの多くのアカウントを削除したと発表しているが、われわれはこう言いたい。できることはそれだけか？われわれはお前とは格が違う。お前がアカウントを1つ停止したら、われわれはお返しに10個消し、すぐにお前たちのサイトを削除して、お前たちの名前は消されるだろう、アッラーの意志による。すぐにわれわれの言うことが正しいことを知るだろう。
Twitterと同社CEOが、過激派をプラットフォームから追放しようとしてISIS支援者の標的にされたのはこれが初めてではない。昨年3月、Twitter社員とDorsey個人を脅迫する投稿がネットに出現した。
Vocativによると、ビデオはメッセージングアプリのTelegramによって掲載された。ジョージワシントン大学が実施した、あるISIS支援グループの主要ソーシャルメディア利用状況に関する最近の調査によると、TelegramはTwitterを追放された過激派がバックアップとして好んで使われている。
本誌はTelegramに、同アプリで見つかったビデオに関するコメントを求めている。TwitterとFacebookにも連絡を取ったが、本稿執筆時点で回答はない。
Telegramは、ISIS宣伝活動に対して独自の対抗策を講じており、一連のISIS支援チャンネルを昨年11月に閉鎖した。チャンネルは過激派によるISIS支援コンテンツの配信に利用されていた。
しかしジョージワシントン大学の調査によると、ISIS支援者らはTelegramのグループおよびスーパーグループを使用することで、集団とのコミュニケーションを行っている。ただし、こうした方法では、公開チャンネルや主要ソーシャルメディアほど、広く大衆に募集メッセージを発信することはできない。
[原文へ]
（翻訳：Nob Takahashi / facebook）
（2016年2月27日 TechCrunch日本版「ISIS支援ハッカーグループ、アカウント削除を巡りTwitterとFacebookのCEOをビデオで脅迫」より転載）
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