A second replacement Samsung Galaxy Note 7 device, deemed safe by the company, has caught fire in the US, US media report.
Samsung has been forced to issue new models of the smartphone following complaints of faulty batteries.
A man in Kentucky said he was “scared to death” when he woke to a bedroom full of smoke, local media say.
It comes after another replacement Note 7 caught fire on a Southwest Airlines plane on Wednesday.
“The phone is supposed to be the replacement, so you would have thought it would be safe,” Michael Klering of Nicholasville, Kentucky, told local broadcaster WKYT.
He added that his device was not plugged in when it caught fire at his home on Tuesday.
The BBC’s North America technology reporter Dave Lee says Samsung is now facing a “full-blown crisis”, adding that this latest news raises “serious questions over its obligation to protect the public”.
The Note 7 was subject to a mass recall in September, but Samsung said it had identified and fixed the problem.
Smoke on a plane
On Wednesday a replacement Note 7 caught fire on a Southwest Airlines plane due to fly from Louisville, Kentucky, to Baltimore, Maryland.
A Southwest Airlines spokesperson told the BBC: “A customer reported smoke emitting from an electronic device. All customers and crew deplaned safely via the main cabin door.”
The plane was evacuated before take-off and Samsung said it was investigating the incident.
“We are working with the authorities and Southwest now to recover the device and confirm the cause,” the company said in a statement.
“Once we have examined the device we will have more information to share.”
Last month the company assured customers that the fixed devices were safe.