The message
from "Clot" contains these words:

Sailing round offshore turbines could be fun.

Ahoy there small sailing vessel approaching down wind. This is the
anti-terrorist protection unit broadcasting on a frequency you won't be
listening to. We have you in our sights and if you don't turn round and
head up wind at least as fast as you are now travelling in this
direction we will blow you out of the water without further ado. You
have 20 seconds to comply with this message. :-)

--
Roger Chapman