yes and we cannot get rid of him , "Luca" kept registering we deleted him first time , he joined again this time we did not get choice to not accept him , we deleted , then third time again we had no disallow membership option and cannot delete the blank face avatar
The only way you can do anything is to use your founders tools >> Forum Utilities do a restore of when the account was made then delete the account your self.
Advice: This is not a good move as older account's may be restored and newer posts and members may be removed in the proses.
I would not worry to much if the posts are not spam and the old account is not making any problems as such.