Lubbock police on Thursday responded to the Budget Motel when two guests who were scheduled to check out could not be reached in their room.
Investigators say the man was dead at the scene. The woman was transported to a Lubbock hospital.
Fire Rescue Battalion Chief Rob Keinast says a faulty heater may be to blame. He says high levels of carbon monoxide were detected in the room.
Names of the man and woman, who checked into the motel Wednesday night, were not immediately released.
The Budget Motel was closed Friday and no one from the business was immediately available to comment.
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