A Southwest passenger says they felt their lungs 'burning' after the cabin filled with smoke mid-flight

• A Florida-bound Southwest flight was forced to make an emergency landing in Cuba on Sunday.
• The plane's cabin filled with smoke after the Boeing 737 was hit by birds.

A Southwest Airlines passenger said they felt their lungs "burning" after the cabin filled with smoke on a flight from Cuba to Florida.

On Sunday, Southwest flight 3923 from Havana to Fort Lauderdale was forced to make an emergency landing after suffering bird strike damage, the airline and the Cuban aviation regulator said.

A video shared on social media that appears to have been taken during the flight shows the cabin filling up with smoke while passengers start to panic.

Marco Antonio, a passenger on the flight, told NBC's "Early Today" show that people on board the Boeing 737 jet were "screaming," adding: "Nobody could breathe. It was burning so much in the lungs."

A spokesperson for Southwest told Insider the plane's engine and nose were struck by birds, which prompted an emergency landing. They said: "The pilots safely returned to Havana where the 147 customers and six crew evacuated the aircraft via slides due to smoke in the cabin."

Cacsa, Cuba's civil aviation authority, said Sunday that the Southwest jet landed at José Martí International Airport in Havana and passengers were evacuated. The regulator said in a Facebook post that the incident was being investigated.

Southwest said all passengers were accommodated on alternative flights to Fort Lauderdale, adding: "We apologize to our customers for the negative experience, extending compensation for the inconvenience and offering additional support."

Representatives for Cacsa didn't immediately respond to Insider's request for comment, made outside normal business hours.

In October, a United Airlines flight was forced to return to Chicago O'Hare International Airport after experiencing a bird strike. Witnesses on board the flight reported seeing flames shooting out of the plane's engine.