Scare in the sky after passenger jet engine suffers major malfunction

A flight from New Orleans to Orlando turned terrifying Saturday after an engine suffered a major engine malfunction and serious damage in mid-air, forcing the plane to divert and causing some passengers to fear they were under attack.

Southwest Flight 3472 with 99 passengers and five crew members on board landed safely in Pensacola at around 9:40 a.m. after the engine failure which occurred at cruising altitude, the airline said.

Passengers said they heard a loud boom and saw smoke trailing from the left engine, and saw metal flapping after the smoke cleared.

Oxygen masks dropped, and passengers later saw a jagged gash in the body of the plane. Emergency vehicles were on standby as the Boeing 737 landed.

This photo taken by a passenger on Southwest Flight 3472 shows a damaged engine after an engine failure that occurred at cruising altitude Saturday, Aug. 27, 2016.

"A lot of people were crying; I was crying. Especially after all was said and done and hearing how it could have been way worse than what it was," Julie Stevens told NBC station WESH after they later landed in Orlando.

"I thought it was an attack and that the plane was going to go down," she said.

The plane left Louis Armstrong International Airport in New Orleans shortly after 9 a.m., and landed without incident, Southwest spokesman Chris Mainz said. The plane suffered "a mechanical issue with the number one engine," the airline said.

The plane was bought in 2000, Mainz said. What caused the engine malfunction is still under investigation, the airline said.

"We believe it was an isolated incident," Mainz said. The airline will give passengers full refunds as well as $500 vouchers, he said. The plane landed in Orlando at around 5 p.m.

The National Transportation Safety Board said it will investigate the "uncontained engine failure."

Passengers praised the captain and crew for keeping everyone calm.

"Looking at the plane afterwards and seeing that there was a large gash in the back of the plane ... had that punctured the interior cabin we'd be dead," Tammy Richards, of Oklahoma City area, said.

"We had an amazing crew," she said.

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