This is a tactic that is taught and trained and well documented by law enforcement agencies in Texas such as the DPS. Acc to their investigations dating back to 2008, it was among the tactics taught by UT professors at the Monkeywrench bookstore in Austin. https://twitter.com/mrandyngo/status/1297297543810838529

UT students were among those taking lessons in how to defecate and urinate in a bucket, wrap it up and store it to hurl at police. The Monkeywrench is one of many such bookstores that functions as a center of anarchist ideology and training. For a full list...

Go to the Slingshot Collective to see many bookstores in this network. You can sign up for events but there is a vetting process. There is no excuse for journalists reporting that Antifa is a far-right fantasy. They are complicit in a lie that threatens journalism itself.