"According to Harrisbirg 100, at least one “Antifa” group began informing supporters that they intended to burn Confederate and American flags in the town. The site cited an EventBu page advertising the protest. The event listing, though, was soon deleted."
http://www.breitbart.com/big-government/2017/06/27/leftists-promising-to-desecrate-graves-and-protest-during-154th-anniversary-of-battle-of-gettysburg/