Details emerge of how Samsung will retrieve more than 100,000 potentially dangerous phones. Meanwhile, the U.S. authorities are investigating a reported fire involving a 'new' Note 7.

With the Galaxy Note 7 recall progressing, and Samsung resuming sales in the U.S. and South Korea, we're starting to learn exactly how Samsung will get some of the unsold Note 7s in the U.S. back to its Korean headquarters. Fierce Wireless reports that Samsung has obtained a hazardous materials permit from the U.S. Department of Transportation's Pipeline and Hazardous Materials Safety Administration, allowing it to ship 137,000 unopened Galaxy Note 7 devices from U.S. retailers back to Korea.

According to the permits that Samsung applied for from the DoT's Pipeline and Hazardous Materials Safety Administration, the company cannot ship the gadgets via airplane, and likely will use specially designed shipping boxes to move the returned Galaxy Note 7 smartphones from retailers like Verizon and Best Buy back to Samsung's facilities.

The PHMSA says two permits were issued to Samsung on September 7 and 15. The first provided "a quantity-limited, thermally insulated outer package designed to contain fire or smoke," and the second allowed "un-opened Samsung Galaxy Note 7 smartphone devices from retail locations back to Samsung via truck, rail, and cargo vessel," adding that transporting the phones via air was not permitted.

As anyone who's traveled by air since the Note 7 recall began will know, many airlines and aviation authorities continue to ban the use or charging of Note 7s onboard airplanes, even as "safe" models get to consumers through the recall program, and Samsung recommences sales.

Meanwhile the U.S. authorities have begun investigating yesterday's report of a "safe" Note 7 catching fire during boarding on a Southwest airplane. According to The Verge, the phone was switched off when the incident occurred, which prompted an evacuation of the plane. The outlet later reported that the phone was a post-recall Note 7 bought from AT&T, confirming the telltale black square on the box, and checking the unique IMEI number on Samsung's website.

Pictures published by The Verge appear to show a pattern of scorch marks similar to those seen in recalled Note 7s.

In an emailed response to Techno Buffallo, U.S. Consumer Product Safety Commission (CPSC) chairman Elliott F. Kaye said:

CPSC is moving expeditiously to investigate this incident. Thankfully, reports indicate that all of the passengers were able to make it off the plane without harm. Agency staff has already reached out to the FAA and Samsung to gather the facts about the incident. Agency staff will also reach out to the consumer who experienced a serious incident with his phone. I want to reiterate my call for consumers who have the recalled Galaxy Note 7 to keep their smartphones powered down and to immediately take advantage of the remedies being offered by Samsung. Consumers should know that one of the remedies is a refund.

After initially claiming there was "no evidence" that a new Note 7 was responsible for the incident on the Southwest flight, Samsung late last night offered an updated statement:

Until we are able to retrieve the device, we cannot confirm that this incident involves the new Note 7. We are working with the authorities and Southwest now to recover the device and confirm the cause. Once we have examined the device we will have more information to share.

This remains an isolated report in which we don't yet know all the facts. In recent weeks Samsung has investigated overheating reports from new Note 7s in China, which it has blamed on "external heating" from outside the device. For its part, the manufacturer has strenuously asserted that the new Galaxy Note 7 is safe to use.

But needless to say, the possibility of a verified safety issue with "new" handsets would be catastrophic for Samsung, worsening an already dire situation and likely killing the Note 7 for good.