WASHINGTON (AFP) - Rescuers are searching for a father and his three teenage children who went missing off Florida's Gulf Coast aboard a 9m sailboat on Sunday (June 19), the United States Coast Guard said.

The man, his two sons aged 13 and 15 and 17-year-old daughter were last heard from Sunday morning, the Coast Guard said in a statement on Monday night.

They left Sarasota, Florida and headed south for Fort Myers on Sunday before the man called his brother to report heavy seas, saying he saying he was attempting to survive with his children, the statement said.

They were last seen on Sunday morning near Englewood, around 80km from their destination, the Coast Guard said.

The Coast Guard said it had launched air and sea rescue crews to search for the missing family.

Officials have not released their names.