First of all here is a video.
. Second it just start randomly, im level 9 picking up level 30 gear. so im guessing the enemys power spiked for some odd reason, it could be the delemain cab quest trying to collect his cabs
I've noticed the enemies to be very, very tough sometimes. I will blast two whole automatic weapon clips in a guy's face and he still lives while he just hacks in and overheats me to death. I haven't experienced that difficulty everywhere, but definitely in one of the early missions.