RedactedNarrative: V1 was heading northbound 1/4 mile offshore of Boca Raton, FL with six people on board to go fishing.  While the vessel was still in motion, the vessel operator (OP1) noticed the vessel's engine was not responding to the throttle.  He mentioned it to the passengers in the rear of the vessel and they observed water coming into the vessel.  OP1 called a friend who was fishing nearby to let him know they were taking on water.  As the victim (VICTIM) was attempting to hand out life jackets, the vessel capsized and everyone was ejected into the water.  OP1's friend responded to the area and retrieved everyone but VICTIM from the water.  VICTIM was not seen after the vessel capsized.  USCG, FWC, and Boca Raton PD, are conducting an active search for VICTIM.