Location: Large Hardware Store in the Docks
Characters involved: Leader, medic, scavenger
Problem: Pipe bomb glitch
Problem description: I was done looting the place and was heading back to the green evac zone. Scavenger and Medic were already in the green zone. I selected Leader and clicked the green zone. The white circle appeared and he started to run toward it. While he went, I had Medic heal Scavenger (to get points toward the “heal 100k points of damage” achievement). Suddenly the game lagged for a second. When it stopped lagging, a grenade blast activated in the green area. Scavenger was killed and Medic was badly injured. Leader wasn’t in the green zone yet so wasn’t hurt. I clicked back to Leader, and his grenade was gone.
tl;dr: Leader apparently decided to bomb his comrades before he got to the exit.