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,

The discovery came after the flight, which originated in Chicago, landed in Hawaii. The death is under investigation.