PHOENIX - Officials say a flight headed to Texas was diverted to Phoenix Sky Harbor Airport due to an unknown threat Thursday night.
A Sky Harbor spokesperson said United Airlines Express flight 5573 was traveling from San Francisco to San Antonio when it was diverted to Phoenix around 4:45 p.m.
A government official told ABC15 someone found the word "bomb" in the bathroom of the plane.
It is unclear at this time if the word was in a note or written some other way.
Forty two passengers, two pilots and two flight attendants were taken off the plane while police and a bomb squad swept the aircraft.
"Well it's extremely serious," said Sgt. Steve Martos with Phoenix police.
"This is one of those situations where out of abundance of caution, we prefer to go through this process, this tedious process, and that there is no actual viable threat, rather than allowed to continue and something actually occur."
Officials said the investigation did not affect air traffic or any other airlines.
Passengers were re-screened in preparation for their flight to San Antonio, which left around 8:30 p.m. according to airport spokeswoman Deborah Ostreicher.
Phoenix police and the FBI will investigate the incident.