US safety authorities have launched a formal recall of Samsung Galaxy Note 7 phones after reports that faulty batteries led to fires and explosions in the devices.
The Consumer Product Safety Commission said it was recalling the phones "because this product presents such a serious fire hazard" and urged consumers to take advantage of the recall.
Elliot Kaye, chairman of the safety body, said:
Anybody who thinks that a company going out on its own is going to provide the best recall for that company, and more importantly for the consumer, needs to have more than their phone checked.
Samsung, the world's biggest smartphone manufacturer, has sold 2.5m Galaxy Note 7's already — including one million in the US.
The South Korean tech giant had already announced a voluntary recall at the beginning of this month, following reports that 35 phones' batteries had gone up in flames while charging or in normal use.
By the time it issued the recall, the device had only been on sale for a few weeks and was only available in 10 countries, quashing the company's goal to provide a significant competitor to Apple's new iPhone 7.
The Note 7 was lauded as being even more advanced than the most recently available iPhones, featuring eye-scanning technology that moved a step beyond Apple's use of biometrics.