Police are investigating the discovery of a dead body in the wheel well of a United Airlines plane after it landed in Hawaii, the airline and the Maui police department said in statements on Wednesday.

The body was found in the wheel well of one of the main landing gears on flight 202, which arrived at Kahului airport from Chicago on Tuesday, United said in an emailed statement.

The airline said the wheel well of the Boeing 787-10 was only accessible from the outside of the aircraft, and that it was unclear how or when the person accessed it.

In an emailed statement, the Maui police department said it was “actively investigating” the discovery of the body.

The flight left Chicago’s O’Hare airport on the morning of Christmas Eve and the body was discovered after the plane touched down at Hawaii’s Kahului airport. Before leaving Chicago, the plane had previously flown from São Paulo in Brazil.

There is not yet any information as to the identity of the deceased.

Maui police said in a statement: “The Maui Police Department is currently conducting an active investigation regarding a deceased individual discovered on an incoming flight from the mainland this afternoon.”

Associated Press contributed to this story