A Frontier Airlines flight from Seattle was evacuated at Denver International Airport on Monday after crewmembers discovered two threatening notes on board, but police later determined the threat was not credible.
Flight 3406 landed safely at DIA around 11:15 a.m., about an hour behind schedule.
Frontier said the crew found the notes during the flight and immediately notified law enforcement.
Upon landing, the aircraft was met by emergency responders, including police officers, bomb technicians, and K9 units.
All passengers were evacuated and transported to the terminal by bus while authorities conducted a security sweep of the aircraft.
“The plane has been cleared and the threat appears to be unfounded at this time,” the Denver Police Department said in a statement, directing further questions to the FBI.
Later Monday afternoon, the FBI’s Denver field office confirmed that no evidence of a credible threat had been found, though the agency did not release additional details.
Passenger Roy Taylor, speaking from the airport’s baggage claim area, said he noticed something was wrong based on how the plane landed.
“Something happened that definitely spooked the pilot and the crew,” Taylor told CBS News Colorado. “When they landed, the plane stopped really fast, and then kind of like a hard right, and I knew the airport terminal was on the left.”
Taylor said he wasn’t initially worried but sensed some panic. He praised how passengers stayed calm despite the uncertainty.
Kelsey Hines, another passenger on the flight from Yelm, said communication from officials was limited and she learned most of the details from news coverage.
“Before reading the article on CBS, we thought there was a bomb on board,” Hines said. “There was bomb people, bomb dogs, the whole shebang… just giving us a heads up about what the process was would’ve been nice so we weren’t all concerned as to what was going on.”
She was on the flight with her 14-year-old son.
While she is happy to be home, Hines wished for more transparency from the airline and investigators about what was going on.
“If it was directed at a specific person or the whole flight or the whole airport itself. We don’t know anything,” Hines said. “And you are in buses with all of these people from your flight. You don’t know if that person is on the bus with you,” she continued.
Frontier Airlines confirmed in a statement that the notes were found mid-flight and that all procedures were followed to ensure passenger safety.
“On Monday, July 28, as Frontier flight 3406 was en route from Seattle-Tacoma International Airport (SEA) to Denver International Airport (DEN), crewmembers discovered two threatening notes on the aircraft. Law enforcement was promptly alerted, and the flight landed safely at DEN. A security sweep of the aircraft resulted in no findings of concern and the aircraft has been released back into service. Passengers were transported to the terminal via bus to be reunited with their luggage and/or continue with their travels,” Frontier said in a statement.
The FBI continues to investigate the source and content of the notes.
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