The U.S. Coast Guard said five people are missing from a capsized vessel about 29 miles off the St. Lucie Inlet.
Coast Guard crews rescued four people from that boat on Sunday.
One of those rescued told officials the vessel actually capsized on Friday.
The search for the other five people is ongoing.
St. Lucie Inlet is located between Hutchinson Island and Jupiter Island in Martin County, Florida.
The inlet is one of six into the Indian River Lagoon. South of the inlet is the St. Lucie Inlet State Park, featuring hard and soft coral reefs.
