"Out of an abundance of caution, the aircraft diverted to Raleigh-Durham and both passengers and crew exited the aircraft via evacuation slides," the spokesperson said.
RDU officials said 102 people were evacuated from the aircraft.
One passenger was medically evaluated and taken to WakeMed. No other injuries or health issues were reported.
RDU officials said the airport was contacted about 5:45 p.m. by Frontier Flight 1159 with a need to divert. When the plane arrived, RDU Fire Rescue responded along with Wake EMS, Raleigh Fire, Wake County Fire Service and Wake County HAZMAT.
There was no indication of a fire on the aircraft, Frontier Airlines said.
All passengers made it safely inside the airport terminal. Frontier is working to get them to their destinations.
The airport remained open throughout the event; however, the Terminal 2 ramp was closed briefly but reopened around 7:20 p.m.
RDU officials said approximately 16 arrival flights were unable to access a gate for at least an hour because of the terminal closing, which was done as a cautionary measure.
Airfield operations have returned to normal.
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