MARTINSVILLE, Ind. (AP) — Authorities are searching for a man missing since a Labor Day boating accident on a central Indiana river that left four other people dead, including a 6-year-old boy.

Two of the boat's seven occupants made it to shore Monday night, but the boy identified as Amisadai Elel Conchas and 73-year-old Emilia Villegas of Mexico were pulled from the White River near Martinsville by emergency responders that night and pronounced dead.

The Indiana Department of Natural Resources says the bodies of 63-year-old Niseforo Sanchez of Mexico and 40-year-old Rigoberto Conchas of Indianapolis were found Tuesday. A search for 32-year-old Antonio Sanchez-Maldonado of Indianapolis continued Wednesday.

The victims were members of a family celebrating the holiday with a cookout and fishing trip. It's unclear what caused the flat-bottomed boat to capsize.