BEIJING (REUTERS) - Tesla will update its battery software after two recent fires involving its Model S electric vehicles (EV) in Shanghai and Hong Kong, the United States automaker said, adding that investigations into the incidents are ongoing.

"As we continue our investigation of the root cause, out of an abundance of caution, we are revising charge and thermal management settings on Model S and Model X vehicles via an over-the-air software update that will begin rolling out today, to help further protect the battery and improve battery longevity," Tesla said in a statement on Wednesday (May 15).

On Tuesday, Hong Kong's Apple Daily newspaper reported that a Tesla car caught fire in a shopping mall carpark 30 minutes after being parked.

Tesla said its investigation with the authorities into that incident so far found only a few of the car's battery modules affected and that the majority of the battery pack was undamaged.

The Hong Kong incident came three weeks after Tesla said it sent a team to investigate a video on Chinese social media that showed a parked Tesla Model S car exploding in the commercial hub of Shanghai.

There have been at least 14 instances of Tesla cars catching fire since 2013, most of them following a crash.