ON JUNE 6 2012 @ APPROXIMATELY 0540 HRS. UNIT 1 WHILE TRAILING APPROXIMATELY 150 YARDS OFF STERN OF SPORT FISH "REEL HOOKER" WAS TRAVELING EAST IN CHARLESTON HARBOR CHANNEL TOWARDS CHARLESTON JETTIES WITH 3 PEOPLE ABOARD. UNIT 2 LEFT JAMES ISLAND YACHT CLUBDOCK WITH ONE PERSON ABOARD HEADING NORTHEAST ACROSS CHARLESTON HARBOR TO PICK UP CREW TO GO OFF SHORE FISHING. AFTER CROSSING WAKE OF SPORT-FISHING VESSEL, UNIT 2 PORT SIDE BOW COLLIDED WITH UNIT 1 STARBOARD-SIDE BOW, CAUSING BOTH VESSELS TO SUSTAIN EXTENSIVE DAMAGE. UNIT 2 DID NOT SEE THE BOAT COMING AND THE OCCUPANTS WERE IN THE CABIN. DUE TO THE COLLISION, BOTH VESSEL OCCUPANTS RECEIVED INJURIES DUE TO FALLS IN THE BOAT.