Flight 448 had just taken off Monday afternoon when the pilot heard banging from down below. The airline said in a news release the captain immediately returned to Seattle-Tacoma International and declared an emergency for priority landing.
After the plane landed a ramp agent was found inside the front cargo hold, which Alaska says is pressurized and temperature-controlled. The airline says the worker, an employee of Menzies Aviation, told authorities he had fallen asleep.
The worker walked off the plane and appeared OK, but was taken to a hospital as a precaution.
Alaska says it's still investigating the incident.
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Alaska Airlines flight returns to Sea-Tac after ‘banging' heard in cargo hold