Dhaka: An Air China passenger flight en route to South Korea was diverted on Saturday (Oct 18) after a lithium battery caught fire in a carry-on bag stored in an overhead compartment, the airline said.

Flight CA139, which departed from Hangzhou and was bound for Incheon International Airport near Seoul, was rerouted to Shanghai Pudong International Airport following the mid-air incident.

Footage captured by passengers and circulated by local media showed smoke and flames emerging from an overhead bin as cabin crew responded. “A lithium battery spontaneously ignited in a passenger's carry-on luggage stored in the overhead bin,” Air China said in a statement on the Chinese social media platform Weibo.

The airline said the crew acted immediately according to standard procedures and that no injuries were reported.

Thermal runaway — a sudden self-heating of lithium batteries — can occur due to physical damage, overheating, overcharging, exposure to water, or improper packing, according to the U.S. Federal Aviation Administration (FAA).

Devices commonly powered by lithium batteries include smartphones, laptops, tablets, smartwatches, and portable power banks.

While airline policies vary, many carriers ban uninstalled lithium batteries in checked luggage. The U.S. Transportation Security Administration (TSA) prohibits all loose lithium batteries from being placed in checked bags.

Air China has not yet provided further comment as of Saturday.

-B