United Airlines Flight 799 was forced to return to its gate at McCarran Airport on Sunday.
The plane left for San Francisco around 10 a.m. United officials say that an indicator stated there was smoke in the cargo area.
Officials also say the plane returned to its gate at McCarran, and Clark County firefighters were called to the scene.
United officials say that the incident was a false alarm. The plane departed a few hours late.
There were 154 people on board the plane.
Correction: The original version of this story stated that there was smoke in the cargo area, but United officials confirm that the incident was a false alarm. This story has been edited to reflect these changes.