https://arstechnica.com/tech-policy/2018/10/mail-bombing-suspect-repeatedly-threatened-democrats-on-twitter/

Cesar Altieri Sayoc, the suspect in the nationwide bombing campaign against critics of President Trump, regularly took to Twitter to make thinly veiled death threats against other users and peppered some of the targets with abuse, according to a quick review of an account authorities believe belongs to Sayoc. Twitter initially allowed the posts to remain despite its stated policy barring threats.

Former Vice President Joe Biden, actor Jim Carrey, director and former actor Ron Howard, and the TMZ celebrity news service all received tweets from someone using the handle @hardrock2016 that made thinly veiled threats against their lives. Rochelle Ritchie, a political commentator who tweets under the @RochelleRitchie handle, received a similar tweet warning her that “We have nice silent air boat ride for u here on Everglades swamp. We will see you 4 sure. Hug your loved ones real close every time you leave home.” Similar to the tweets sent to others, the message directed at Ritchie included an image of her and accompanying images of the tarot card for death and TV news coverage purporting to report on a body being recovered from the Everglades.