(Reuters) - An air and sea search was underway for a father and three teenage children whose sailboat was reported missing off the coast of western Florida, the U.S. Coast Guard said on Tuesday.

Their 29-foot (9-meter) sailboat was last seen on Sunday morning off the coast near Englewood, Florida, the U.S. Coast Guard Southeast said on Twitter.

The Coast Guard "has launched air and boat crews in search for missing family. Asks public to keep a sharp lookout," it said at about 11 p.m. local time.

The Coast Guard initially said the three children were teenage boys, but later clarified that two boys aged 13 and 15 and a 17-year-old girl were onboard.

(Reporting by Brendan O'Brien in Milwaukee; Editing by Simon Cameron-Moore)