Denali National Park and Preserve officials say a man committed suicide inside the park on Sunday evening.

According to a release sent very early on Monday, National Park Service Rangers investigated a tent near the railroad tracks at approximately 5:45 p.m. An unidentified white male was briefly seen through the tent. Rangers then heard a single gunshot. The man was not visible to rangers when the gun was fired, and there was no response to verbal calls afterward.

Park Service officials then called in assistance from the Alaska State Troopers and the FBI. Shortly before 10:00 pm, the man was found dead, apparently of a self-inflicted gunshot wound.

The investigation is ongoing. The man’s name is being withheld until next of kin is notified.