External battery pack catches fire onboard flight, plane returns to airport

An external battery pack caught fire on a flight that had just taken off from San Diego en route to New Jersey, forcing the flight to circle back and sending several people to the hospital.

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The incident happened Tuesday morning on United Airlines flight 2664, The New York Times reported.

At first, the flight crew reported that a laptop was on fire, but United Airlines said that “a customer’s battery pack ignited.”

It was in a seat-back pocket in first class, ABC News reported.

A spokesperson for the San Diego Fire-Rescue Department confirmed that it was an external battery that caught fire and that crew members put it in a “fire bag” to prevent the flames from spreading.

Four flight attendants were taken to an area hospital for treatment of smoke inhalation, NBC News reported. Two passengers were treated on site, United said, according to ABC News.

Lithium-ion batteries can overheat or cause fires. They are found in everything from laptops to cellphones to toothbrushes, The New York Times reported.

They are allowed on flights but must be put in carry-on baggage. They are prohibited from being packed in checked luggage.

A laptop started smoking on a flight from Barbados to New York in December, according to The New York Post and the Times. A flight from California to Germany had to land in Chicago after another laptop overheated and caused a small fire, WMAQ reported.

The Federal Aviation Administration said there were 57 lithium battery incidents on planes last year, ABC News reported.