SEATAC, Washington (AP) — Two planes have been evacuated on arrival at Seattle-Tacoma International Airport due to what a spokesman calls a "security concern."

Airport spokesman Perry Cooper says a JetBlue flight from Long Beach, California, and a regional SkyWest jet from Phoenix were involved. The flights arrived Sunday afternoon.

Cooper said that out of caution, passengers were bused to their gates. He said the matter was under investigation and did not have further details.

Additionally, a Delta Air Lines spokesman says a flight from Los Angeles to Orlando was diverted to Dallas on Sunday afternoon due to "a security concern."

It was unclear if any of threats were connected. The Federal Aviation Administration didn't immediately respond to messages.

The evacuations come a day after bomb threats targeted two jets bound for Atlanta, prompting F-16 fighter jets to escort the planes.