The Panic Bar is the electronically-controlled bar that remains in place after the intruder yanked the door open. It's not supposed to work that way; it's supposed to keep the door closed unless unlocked from the outside with a code, from the inside with an RF remote, or from the inside by pushing the bar outward (e.g. in a panic).
The panic bar was attached to the door frame via 4 self-tapping screws that just screwed into the sheet metal of the door. When the guy yanked, the sheet metal failed, and the screws just pulled out.
It has now been re-attached with bolts that go all the way through both sheets on the metal door, with security nuts on the outside. You'd have to hack on it for awhile to defeat it, now.
There's also a deadbolt, but typical OP was for the first person to arrive in the morning to unlock the deadbolt and rely on the panic bar during normal business hours. We've amended our SOP so that we don't unlock the deadbolt until there are more people in the building.