The U.S. Consumer Product Safety Commission is urging consumers who have Samsung Galaxy Note7 smartphones to "power them down and stop charging or using" them.
The warning, issued in a news release today, came amid recent news that lithium-ion batteries in certain Note7 devices had resulted in fires.
"When these batteries overheat and burst, the results can be dangerous," the CPSC said in its statement. "These incidents have occurred while charging and during normal use, which has led us to call for consumers to power down their Note7s
The agency said it is working with Samsung to formally announce a recall of the devices.
"CPSC is working quickly to determine whether a replacement Galaxy Note7 is an acceptable remedy for Samsung or their phone carriers to provide to consumers," the agency said.
In a statement today, Samsung asked owners of the smartphones to exchange them for a loaner phone as it hammers out the terms of the recall.