Kristi Noem said she "hated" the dog as it behaved like a "trained assassin," and was "dangerous to anyone she came in contact with"
Another 57 people were rescued in an operation that was still ongoing, the coast guard added.
It did not provide further details on the incident or the nationality of the victims.
Many refugees and migrants attempt to cross the Aegean Sea from Turkey, a short but perilous trip often hit by bad weather.