Five people were killed when their small plane crashed near Denver on Sunday, The Associated Press reports, citing the National Transportation Safety Board.

“At approximately 11:50 this morning we got some eyewitness accounts of a plane crash just north of the airport here,” Lee Mathis, Erie police commander, told CBS4. “The officers responded and found that a six passenger plane had crashed and cordoned off the scene and called the NTSB and now we’re waiting on them to further the investigation.”

The plane, a Piper PA-46, crashed short of the runway at Erie Municipal Airport. Three of the plane’s passengers were reportedly declared dead at the crash site, while two later passed away at nearby hospitals.

Citing NTSB spokesman Peter Knudson, the Los Angeles Times reports that NTSB investigators and local officials are assessing the scene of the accident in order to figure out why the Piper PA-46 crashed.

The plane’s passengers were reportedly flying to the Erie Municipal Airport from Centennial Airport.