According to the help page, e.g. on Stack Oveflow (emphasis is mine):
All the reputation changes from a single user's deletion are rolled into a single event in the reputation page labelled "User was removed".
But I see multiple events in my profile on Stack Overflow in Russian:
One message (20:41) says "User was removed", and the rest (all 20:40) say "unupvote". For most posts unupvoting is not possible due to lack of post edits, i.e. vote should be locked on them. Hence I think it's a bug.