So where is the aircraft? Off the end or 45 degrees off the end or off a taxiway? No mention of braking action on METARS - must be ok. Was this the first arrival of the day? Icy taxiways......... down to airport operator? Or were they too fast? FDR data will reveal all in due course.
Bad luck guys. Could happen to any one of us.
I remember a Britannia 767 (I think) sliding unceremoneoulsy into the grass whilst vacating BHX 15. The last 90 degree turn off had a reputation for being slippery when wet - and it was. Just a couple of knots too fast and laws of physics take over....
A4