KANSAS CITY, Mo. (AP) – Authorities say a woman has died on an Alaska Arilines plane that took off from Seattle and landed at Kansas City International Airport.

Kansas City police said in a news release that firefighters responded Tuesday to a medical emergency on Flight 478 and found the woman dead. Police said it appeared that she had suffered from cardiac arrest but that the exact cause of death won’t be known until after an autopsy.

The airline’s website says the flight was direct from Seattle to Kansas City.

The woman’s name wasn’t immediately released.