I'm here to confirm this as well.

Happened to me only once but like you said it tends to happen when on upper levels of buildings. I died instantly from full health when i ran into a room of school / office-building in the 3th floor. It was one of the small rooms and i ran there sprinting. My friend was already in that room waiting for me to loot a new weapon. There was no shots fired and no damage was done to any of my gear so this seems to be very similar to your report.