freakymess in Scoundrel's Rise

I went out with a team for exp. in Scoundrel's Rise, outside of Gates of Kryta for the lvl 18 (now lvl 17) Scales. This is after I got to Kryta, when all the regular undead disapear. When we were halfway done with the first set of scales, there were 3 lvl 18 undead Executioners marching toward us in the distance. We were able to take care of the scales in time to kill the Executioners, but then a lvl 25 undead horseman boss was marching toward us. To my amazement, we were able to kill that too.

Question is: what the Hell was this? Did somebody in our group have a quest that caused these undead to spawn or was this a fluke?

yeah, its a quest called 'reversing the skales'

Laz