Days after some reports claimed that two iPhone 8 Plus handsets -- one in Taiwan and another in Japan -- had burst open due to the swelling of the batteries, state run media in China reported on Thursday yet another incident of swollen iPhone 8 Plus battery. While the exact cause of the issue is still unknown, Apple has now confirmed that it is investigating the matter.

"We are aware and looking into it," Apple said a short statement on the issue.

iPhone 8 Plus
An Apple employee poses with the iPhone 8 on display at Apple Regent Street during the launch of the new phone on September 22, 2017 in London, England. Apple have today launched their new mobile phone the iPhone 8 and 8 plus in the UK today ahead of the iPhone X's release in November.Jack Taylor/Getty Images

Over the past few days, there have been multiple reports claiming that some iPhone 8 units have split apart either on arrival or after several days of use. This has happened since the battery inside the phone gets swelled for some unknown reason, bending the device's front and separating it from the body.

However, no incident of explosion or fire has been reported so far.

In the first reported incident, which came out of Taiwan, the iPhone 8 Plus user had been using the device for five days, and found it swollen apart after plugging it in to charge. In the second incident, a consumer in Japan received a bloated iPhone 8 Plus with its middle part cracked open.

Although there have been similar cases reported in China, Canada and Greece, the issue seems to be quite small, with only six incidents reported so far in comparison to the millions of new iPhone 8 units that have likely already been sold by Apple.

However, if the iPhone-maker learnt anything from Samsung's Galaxy Note 7 disaster, then it must treat the issue seriously, especially since the iPhone 8 battery is in question.

"[Swelling is] very unusual for a brand-new battery and leads toward the direction of there's something fundamentally wrong with this battery," Sam Jaffe, managing director of Cairn Energy Research Advisors, told The Verge.

In case of the Samsung Galaxy Note 7, several units of the phone caught fire after their batteries exploded while charging, and sometimes when the phone dropped on the floor. The problem was so extensive that it forced Samsung to recall, and eventually discontinue the handset, resulting in great expense.

When it comes to Apple, the issue of swelling batteries appears to be limited to only a few devices, at least so far. But it comes at a crucial time for the company as it's still early days for the iPhone 8 series, and the much-awaited iPhone X is about to reach consumers worldwide.