A KLM Royal Dutch Airlines flight from Sao Paulo was plunged into chaos after a portable phone charger caught fire midair, filling the cabin with thick smoke and alarming passengers.

Brazilian journalist, Simone Malagoli, who was a passenger onboard, described it as “perhaps the tensest flight of my life.”

Terrifying footage captured by Malagoli shows passengers shielding their faces with cloths and tissues, while crew members rushed through the aisle carrying a fire extinguisher.

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“Smoke was detected on board due to a burning power bank,” the airline told People.

“The crew quickly extinguished the device, following established safety procedures. The situation was brought under full control.”

The aircraft, which departed Sao Paulo airport on Tuesday, continued to Amsterdam and landed safely without any injuries.

Lithium batteries, commonly found in portable chargers and power banks, are increasingly implicated in aircraft emergencies due to their tendency to overheat, ignite or even explode under certain conditions.

These incidents can rapidly fill cabins with smoke and force crews into emergency protocols.

Last month, a Delta Airlines flight from Atlanta was diverted for an emergency landing in Florida after a device caught fire in the cabin.

This marked the 34th lithium battery incident on US passenger aircraft this year, according to Federal Aviation Administration (FAA) data cited by Forbes.

According to the FAA, lithium batteries can enter a dangerous state known as thermal runaway, a rapid uncontrollable increase in temperature that can lead to a fire or explosion.

This can be triggered if a battery is damaged, overheated, exposed to water, overcharged, or improperly packed.

Because of these risks, airlines require all spare lithium batteries, including those in power banks, to be transported in carry-on baggage only, where crew members can respond quickly in the event of an emergency.