The messages included a comment posted from an account in the name "Calum Thwaites", which is the same name as the 24-year-old student from Queensland University of Technology who has filed a defamation suit against Butler for comments she made on the ABC's Q&A last month.

“This is a coarsening of public debate and we should be very, very worried about it,” Butler said.

BuzzFeed News has now obtained screenshots of the post.