Passengers evacuated from an Air Busan plane that was engulfed in flames this week at a South Korean airport will have their checked baggage returned to them, after authorities on Friday deemed the jet safe for a full investigation.

The authorities decided to proceed with the joint investigation to determine the cause of the recent blaze aboard an Air Busan without first removing the aviation fuel, the Transport Ministry announced Friday.

Concerns have been raised about the safety risk of bringing portable batteries in carry-on luggage for flights, as a lithium-ion battery is suspected as the cause of the fire that