The video at the top of this page and the photos below show protesters, identified by the Associated Press photo captions and by social media accounts as Morsi supporters, forcing an armored Egyptian state security vehicle off the side of the 6th of October bridge.
The truck drops what appears to be the equivalent of several stories and flips upside-down before slamming violently into the ground. It's not clear whether or not people were in the truck at the time, but a subsequent photo shows two security officials splayed, one on the truck's now-skyward underside and another on the ground nearby.
The video also shows several protesters rushing toward the truck, although it's difficult to tell if they were rushing to help or to grab the security officials. Either way, it is another shocking moment of violence in a day that's had many.