An unidentified man collapsed and died Tuesday morning on the Bright Angel Trail in Grand Canyon National Park.

Park officials say that at roughly 10:45 a.m. the Grand Canyon Regional Communications Center received a 911 call of a man unconscious on the Bright Angel Trail approximately two-and-a-half miles below the rim.

Emergency personnel responded from the 1.5-mile resthouse on the trail and began CPR on the man. "Additional rangers were flown in and CPR continued for approximately one hour. Their life-saving efforts proved unsuccessful and the man was declared deceased on scene," a park release said.

The man’s body was flown by helicopter to the South Rim Helibase and transferred to the Coconino County Medical Examiner. An investigation into the incident was being conducted by the National Park Service in cooperation with the Coconino County Medical Examiner.

Additional information regarding the deceased man was to be released after family notifications have been made.