Board Thread:Show-Related Questions and Answers/@comment-25526130-20141118053958/@comment-25125349-20141118055729

They probably can be unfrozen. However Regina seemed worried Marian's heart would eventually freeze over time so they removed it. But then there might be a distinction on a peron being frozen on purpose or not.

If that is the case, things look bad for Hans, but not for Kristoff and Anna (and whoever else was in the palace)