The search resumed Monday morning for a man in his 40's who jumped in the St. Johns River in the Ortega area Sunday afternoon.
Lauren Hallacher with our partner Action News reports search crews called off the search around 11 p.m. on Sunday with still no sign of the man.
We are told the man was with five other people on a boat when he went in the water to cool off.
"An individual was boating on the water all day long, he stopped the motor and went in the water for a swim and immediately the people who were still on the boat noticed that he was in distress," said Sharon Scott with the Jacksonville Sheriff's Office.
Scott said the people still on the vessel threw the man a life line but he never resurfaced.
Helicopters were seen flying over the water near Riverside looking for any sign of the man.
"The family said he was a strong swimmer. We have to see what happened, he could've hit a rock, he could've had a heart attack," said Tony Wright with Florida Fish and Wildlife.
Wright said they are treating this as a boating accident because the vessel was not anchored when the man went into the water.
Investigators said the boat belongs to the missing man, whose name was not released by police.