Samsung Galaxy Note 7 devices -- which are known to catch fire -- are being banned from all U.S. flights by the Federal Aviation Administration, according to a federal official.
The government agency is expected to announce the emergency order Friday, which will go into effect Saturday at noon (Eastern Standard Time).
The FAA had previously urged passengers to turn off their Galaxy Note 7 smartphones -- and not charge their batteries -- while on a flight.
This ban now puts Galaxy Note 7 smartphones on the long list of items banned from flights, such as lighter fluid, electronic cigarettes and hand grenades.
The FAA's critical move comes four days after Samsung told customers worldwide to turn off their phones -- an unprecedented warning for an extremely popular smartphone.
Samsung released the 5.7-inch Galaxy Note 7 device in August as a competitor to Apple's new iPhone 7. But customers immediately started complaining that some phones were catching fire.
The company explained that faulty lithium-ion batteries were overheating the device and causing it to ignite.
The South Korean electronics manufacturer took several steps to limit the damage from its dangerously glitchy smartphone.
In early September, Samsung recalled 2.5 million devices worldwide.
The company offered replacement phones -- but some of those burst into flames too.
In the past week, Samsung halted production of the device, then announced it was killing off the product line entirely.
But even those returns are running into problems, because Samsung Note 7s are now banned from FedEx, UPS and USPS planes, and FedEx ground collections are tightly restricted.
Samsung is attempting to make itself right with customers, so it's offering customers a full refund -- plus a $100 credit for those who buy another Samsung phone.
The disaster is expected to cost Samsung more than $5 billion. The company's stock, which trades in Seoul, has fallen 4% this week.