Deputy chair of the DNC praises violent left-wing organization in a tweet

Deputy chair of the Democratic National Committee, Rep. Keith Ellison (D-Mich.), posted a controversial tweet that appeared to praise the organization "Antifa," which has been noted for its extremism and violence.

Here's what he posted:

At @MoonPalaceBooks and I just found the book that strike fear in the heart of @realDonaldTrump pic.twitter.com/r81nYoeqpL

— Rep. Keith Ellison (@keithellison) January 3, 2018

The tweet reads, "At @MoonPalaceBooks and I just found the book that strike[s] fear in the heart of [President Donald Trump]" with a photograph of the book, "Antifa, the anti-fascist handbook."

What is "Antifa?"

"Antifa" is short for "anti-fascist," as the organization fashions itself as the opponent of any kind of fascism. In practice, however, the term has "fascist" has been applied to any stripe of conservative no matter how moderate or mainstream, and the opposition has often included violence.

Antifa members have shouted down conservatives and "alt-right" advocates at speaking events, some of which turned into destructive rioting. Some have called for the organization to be designated a "terror group" for its numerous acts of violence.