Apple Inc. (NASDAQ:AAPL) has said it is looking into reports of iPhone 8 Plus handsets bursting open due to swollen batteries.
In the past week there have been six reports about the battery inside the phones expanding soon after first use, causing them to split open.
The first indicident emerged in Taiwan and similar problems have been reported in Japan, China, Canada, Greece and Hong Kong. It is unclear whether the issue is with a few select phones or a wider problem.
Apple news site MacRumours, which reported the first case, said it was common for there to be a “very low percentage of defective units” given the large quantity of iPhones manufactured.
However, Cairn Energy Research Advisors analyst Sam Jaffe said in a blog that the swelling of batteries so soon after product launch was troubling since it was a problem that usually happened at the end of a battery’s useful life.
"It could be a minor distribution of a random manufacturing error," Jaffe wrote.
"If it's a little bit more than that, Apple might quickly be able to identify the battery manufacturing line that's responsible, shut it down and keep making iPhone 8s without any more issues.”
Apple said it was investigating what might have caused the issue.
Rival Samsung last year recalled its Galaxy Note 7 smartphones after reports of batteries overheating and catching fire.
Reports of iPhone X delay inaccurate, says Citigroup
Apple has also had to contend with media reports that the iPhone X could be delayed beyond the November launch date.
Analysts at Citigroup said such claims were inaccurate and that they were “confident” the iPhone X will be released on time.
However, the analysts think "sub-optimal production yields" will lead to demand outstripping supply and sales estimates that are below current consensus forecasts.
Citigroup expects "volatility" in Apple’s shares in the near term but repeated a ‘buy’ rating, saying customers waiting for the iPhone X will pave the way for 2018 results ahead of expectations.
Shares in Apple rose 0.35% to US$155.85 each in US pre-market trading.