 Complete the following phrase:  The Luftwaffe had a few anti-shipping naval units such as 4.StTrGr 186 to deal with Polish naval forces. This unit performed effectively, sinking the 1540-ton destroyer Wicher and the minelayer Gryf of the Polish Navy both moored in a harbour. The torpedo boat Mazur 412 tons was sunk at Oksywie; the gunboat General Haller 441 tons was sunk in Hel Harbour on 6 Septemberduring the 