No one was injured Tuesday afternoon, but passengers said flight attendants paced throughout the haze-filled plane with fire extinguishers. Children cried and passengers prayed.
"That was the worst anguish - when they say we are going to land and you look out the window and you see the ocean," said Mayi Antillon, 38, of San Jose, Costa Rica.
Flight 2191 landed at about 2:45 p.m. at the Key West Naval Air Station at Boca Chica Key, airline spokeswoman Martha Pantin said.
The pilot and crew only smelled smoke and did not see it, Pantin said. But several passengers, who said the trouble began just as the crew started to serve food, saw a slight fog in the cabin.
Pantin said another Boeing 757 was sent to the island to pick up the passengers and take them to Cancun. The evacuated jet will be taken out of service and returned to Miami International Airport to be inspected by airline maintenance workers.