Plenty of questions still remain two days after authorities discovered a dead body in the wheel well of a United Airlines aircraft in Hawaii.

A body was found in the wheel well of a United Airlines flight that departed Chicago’s O’Hare International Airport on Christmas Eve, the airline said in a statement. The body was found in the wheel well of one of the Boeing 787-10 aircraft’s main landing gears upon arrival in Maui,

At this time, it is not clear how or when the person accessed the wheel well,” the airline said, noting it is working with law enforcement on the incident.