Safety investigators are looking into another incident of a lithium battery overheating on board an aircraft, this time involving an iPhone 4 carried on an Australian Regional Express Airline (Rex) Saab 340B. The most recent incident occurred Nov. 25 on Rex Flight ZL319 shortly after the aircraft landed in Sydney following a flight from Lismore.

The airline reported the iPhone “started emitting a significant amount of dense smoke, accompanied by a red glow, and was dropped to the cabin floor.”

The iPhone 4 uses lithium ion batteries, which have been implicated in overheating incidents in laptop computers and other personal electronic devices, leading FAA to issue a series of warnings and guidance about their carriage on airplanes.

The flight attendant reportedly used a fire extinguisher on the hot and smoking phone. The company said the passengers and crew were unharmed.

Rex reported the incident to the Australian Transport Safety Bureau (ATSB), as well as the Civil Aviation Safety Authority, for investigation and turned over the iPhone to the ATSB for analysis.