Incident
According to Federal Aviation Administration officials, a passenger mistakenly picked up a backpack containing a Modular Bomb System (MBS) before boarding an airplane. The MBS is a security testing device used for training security personnel. The passenger then boarded the aircraft with the backpack.
During the climb phase of flight, a flight attendant discovered the device and reported it to the flight crew, stating that there was a bag that looked like a bomb. The captain ordered the first officer to verify the flight attendant's observation.
Emergency Response
The captain decided to request an emergency return to Seattle and asked for emergency equipment to stand by upon landing. After landing, the aircraft was directed to a remote location.
Evacuation
The crew performed an emergency evacuation of the aircraft. No further details were provided about the duration of the evacuation or any subsequent actions.