Terror/terrorism — acts of violence or threats used to create fear for political purposes. (More commonly called 'テロ' in Japanese.)
政府はテロル対策を強化すると発表した。
The government announced it would strengthen counter-terrorism measures.
その事件は国内外でテロルとみなされた。
The incident was regarded as an act of terror both domestically and internationally.
ニュースでは『テロ』という語の方がよく使われるが、文語ではテロルも見られる。
In the news, the term 'テロ' is used more often, but 'テロル' can be seen in more formal writing.