A United Airlines flight from San Diego International Airport (SAN) bound for Newark Liberty International Airport (EWR) was forced to return after a laptop battery caught fire onboard.

Flight UA 2664 departed from SAN airport on February 7, 2023 and was in the air for roughly 10 minutes, when a passenger’s laptop battery pack ignited in a backseat pocket.

United crew members contained the blaze by placing the burning item into a thermal containment bag.

According to flight tracking website FlightAware, the flight returned at 07:51 local time. The plane returned to the gate in San Diego Airport’s Terminal 2, and first responders arrived at the scene.

United said that four flight attendants were taken to hospital, while two passengers were evaluated on-site.

The flight later departed once more for Newark, and no other operations were reported to have been affected.

“We thank our crew for their quick actions in prioritizing the safety of everyone on board the aircraft and we are making arrangements to get our customers to their destinations,” United said in a statement reported by ABC News.

Lithium batteries, often used to power laptops, have the tendency to overheat and are known to cause issues on planes.

According to the FAA, there are 57 lithium battery incidents on flights in 2022 alone. Firefighters who responded to UA 2664 said that the battery pack was plugged into a passenger’s mobile phone.

The FAA said that it will investigate the incident.