AT&T is discontinuing all sales and exchanges of Samsung Galaxy Note 7 smartphones following a number of fires caused by supposedly "safe" phones that had been replaced under recall.

"Based on recent reports, we’re no longer exchanging new Note 7s at this time, pending further investigation of these reported incidents," said an AT&T spokesperson in a statement to The Verge. "We still encourage customers with a recalled Note 7 to visit an AT&T location to exchange that device for another Samsung smartphone or other smartphone of their choice."

All four of the big US carriers have said they will allow returns of any Note 7, but AT&T is the first to stop sales of the device entirely. The US Consumer Product Safety Commission has said it is "moving expeditiously" to investigate the fires and it seems likely that a full recall of all Galaxy Note 7 devices is imminent.

A Verizon spokesperson told The Verge that the Note 7 is backordered and the carrier has none in inventory to sell. T-Mobile told The Verge that it continues to sell replacement Note 7 phones to customers who wish to purchase it, while Recode says Sprint is offering replacement Note 7 phones to owners of the recalled Note 7. We have also reached out to Best Buy for comment.

Updated 3:05PM ET: Added Verizon comment.

Updated 3:45PM ET: Added Sprint and T-Mobile info..