http://www.winknews.com/Local-Florida/2011-12-28/Boat-sinks-off-Key-West-2-people-rescued-return-to-Ft-Myers

According to the news report they pulled the anchor from the stern
after it became stuck.

"We put it back on the stern to bring it up and we had power on it
and when we had let go, it snatched back and the waves filled the
stern up with water"

It's not clear if it was a low transom boat or not but it sounds like
it might have been.

They were saved by their EPIRB and life raft.