A Frontier flight made an emergency landing at McCarran International Airport Wednesday morning.
The Southern Nevada Fire Alarm website showed an "in flight mechanical or emergency" alert at 7:12 a.m.
Frontier flight 555, an A319 airbus, was headed from Denver to San Diego when it alerted the towers at McCarran about a possible problem with an engine, McCarran spokesman Chris Jones said.
The issue could be as simple as a faulty indicator light or some smoke, Jones said.
The plane landed without incident, he said.
Information regarding the alternate transportation for passengers and how many people were on board was not immediately available.