The Learjet 35, with a Mexican registration, went down about three miles northeast of Fort Lauderdale-Hollywood International Airport, its departure point, and ended up in waters about a mile offshore, Federal Aviation Administration spokeswoman Kathleen Bergen said in an email.
The Coast Guard said in a news release that it had dispatched search-and-rescue crews aboard two vessels, along with a helicopter crew from Coast Guard Air Station Miami. There was no immediate word from the FAA or Coast Guard on the fate of those aboard.
Bergen told The Associated Press the plane was carrying two pilots and two passengers. But she did not immediately identify them or describe the circumstances prior to the plane going down.
She had reported earlier that the plane had gone down about four miles off the coast, but had noted her initial information was preliminary and was still developing Tuesday evening.
The flight had departed for Cozumel, an island off Mexico's Yucatan Peninsula.