At least four people, including children, were rescued and taken to the hospital after their boat capsized near Carlsbad.
Officials say the small boat appeared to be over capacity, with possibly as many as 20 people on board.
The people rescued had to be hospitalized. A man, woman and two children, according to the Carlsbad Fire Department.
The man was transported in CPR status. The young children, around the ages of four to five, were suffering from hypothermia.
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When firefighters and lifeguards arrived, the remaining people in the boat were gone.