A body was discovered in the wheel well of a United Airlines aircraft upon its arrival at Kahului Airport on Maui on Christmas Eve, according to the company.

The body was found in one of the main landing gear compartments, which are only accessible from the outside of the plane. United Airlines officials said they are cooperating with law enforcement in the investigation. It is not clear how or when the person accessed the wheel well, United said in a statement.

The body was discovered shortly after Flight 202 arrived Tuesday at Maui’s Kahului Airport from Chicago.

The Boeing 787-10 departed Chicago O’Hare International Airport on schedule at 9:31 a.m. CST and landed 34 minutes early at 2:12 p.m. Hawaii time, according to FlightAware.com.

The Maui Police Department is investigating.

“The incident occurred yesterday afternoon, and the investigation remains ongoing,” the department said in an email Wednesday to the Honolulu Star-Advertiser. “At this time, no further details are available.”

Wheel wells are unpressurized and exposed to extreme cold and low oxygen levels at cruising altitudes, making survival highly unlikely.

Stowaways in wheel wells have been recorded since at least 1959, according to the Federal Aviation Administration. While survival is rare, there have been a few isolated cases.

The FAA reported incidents where stowaways endured flights from Havana to Madrid or from Bogota, Colombia, to Miami, surviving temperatures as low as negative 65 degrees Fahrenheit and a lack of oxygen at altitudes of 35,000 feet.

However, survival in such cases is the exception, with the FAA noting that about a dozen copycat attempts were made in 1993 alone, many of which resulted in fatalities. The severe conditions in wheel wells — including hypoxia and hypothermia — often prove fatal for stowaways.

There have been examples of stowaways who survived the harsh conditions, and a similar situation occurred on an aircraft that also touched down in Kahului.

In April 2014, a then-15-year-old boy miraculously survived a 5-1/2-hour flight from San Jose, Calif., to Kahului after hiding in the unpressurized front wheel well of a Hawaiian Airlines Boeing 767.

The incident was captured on airport surveillance video, which showed the teen exiting the wheel well upon landing, wearing a hoodie, jeans and sneakers.

The teen, identified as Yahya Abdi of Santa Clara, Calif., told CNN in an interview that he had snuck onto the plane in an attempt to reach his mother, who was living in a refugee camp in Ethiopia.

The FAA had reported that from 1947 to 2014, there were 94 flights worldwide involving 105 stowaways who hid in unpressurized compartments.

Of the 105 people, 80 died while 25 survived. The last known survivor of stowing away in a jetliner’s wheel well occurred in August 2013 on a domestic flight within Nigeria, while the most recent fatality occurred at Dulles International Airport in February 2014, after a flight from Johannesburg, South Africa.

In 2007, Fox News reported a case in which a man died while traveling from China in the wheel well of a jetliner. The body of the apparent stowaway was found in the nose gear wheel well of a United Airlines Boeing 747 that arrived at San Francisco International Airport from Shanghai.

Officials said the man probably succumbed to asphyxiation or hypothermia during the 11-hour flight.