An Alaska Airlines flight made an emergency landing in Seattle on Monday afternoon after the pilot heard banging from within the aircraft, which officials said came from ramp worker who had fallen asleep in the cargo hold.
Alaska Airlines Flight 448, bound for Los Angeles, was in the air 14 minutes before turning around, according to a brief statement released by the airline.
The airline said the agent, an employee of Menzies Aviation, "told authorities he had fallen asleep." A source familiar with the incident told NBC News the worker had apparently taken a nap in the cargo hold and didn't wake up until the plane was in the air.
"The captain immediately returned to Seattle, declaring an emergency for priority landing," the airline said. "After landing, a ramp agent was found inside the front cargo hold, which is pressurized and temperature controlled."
The airline said that the ramp agent "appeared okay" but was transported to a hospital as a precaution.
The incident is under investigation.
This article originally appeared on NBCNews.com.