Verizon announced late tonight that it would no longer offer replacement Samsung Galaxy Note 7 phones to its customers, joining fellow US carriers T-Mobile and AT&T, and other carriers around the world in halting sales of the device. Verizon’s decision comes after it was reported earlier tonight that Samsung was halting production of new Note 7 phones while the investigation is ongoing.

At least five replacement Note 7 phones caught fire in the US alone this week, and federal regulators with the Consumer Product Safety Commission are working to investigate the incidents.

A Verizon spokesperson emailed the following statement to The Verge:

Samsung is working with the Consumer Product Safety Commission to investigate the safety of replacement Samsung Galaxy Note7 smartphones. While the investigation is underway, Verizon is suspending the exchange of replacement Note7 smartphones. Any Verizon customer concerned about the safety of their replacement Note7 smartphone may take it back to the original point of purchase to exchange it for another smartphone. Verizon online customers may also exchange their replacement Note7 smartphones at Verizon stores.

If you own a Samsung Galaxy Note 7 you should immediately stop using it and return it for a refund — all the major US carriers will exchange the phone, regardless of purchase date. We don’t know why Samsung hasn’t been more forthcoming about what’s going on with these replacement devices, but it doesn’t really matter. Until we get more information, the simplest explanation is the best one: the Samsung Galaxy Note 7 is a fundamentally defective product and it should be pulled from the market without delay.