concussion grenades and tear gas shot at people trying to leave

that quote was overheard on police scanners moments before the all-out attack tonight

The protesters were noisy but peaceful as they approached the convention. Once they arrived, a police officer read an order to disperse, CNN reporters on the scene said.

But almost immediately, officers along the exit route opened fire with gas and projectiles. In one instance, a CNN producer said, an officer stepped out of line to hit a young woman with pepper spray as she ran for the exit.

...

Other officers used gas and pepper spray in the path of those attempting to comply with the disperse order, forcing some to stop in their tracks, a CNN crew reported.

on September 2nd, St. Paul police began pepper-spraying, tear gassing and using concussion bombs on non-violent protesters who had been involved in a symbolic parade to the Xcel Center. After the parade ended the police immediately announced that the crowd was an "unlawful assembly," and shortly thereafter began firing chemical irritants