Mark Sinclair was last seen the afternoon of Monday, July 8

West Glacier, MT – Glacier National Park is asking for the public’s help to locate a missing person.

Photo provided by Glacier National Park

 Mark Sinclair, 66, was last seen at approximately 2:30 pm on Monday, July 8 on the Highline Trail at Rimrocks headed west.

Park staff working in the Logan Pass Visitor Center observed him leaving an unsecured vehicle, keys, and dog in the Logan Pass Parking Lot.

 Sinclair was wearing all gray or nondescript clothing (possibly in shorts), a yellow bandanna around his neck, a gray waist fanny backpack, and no hat. His hair is completely white and he may have a beard that is white as well. He is 5’8’’ and approximately 155 lbs.

 If you have information about the missing person, please call 406-888-7077.

 Sinclair is a recent resident of Whitefish, MT, and worked for a period of time earlier this summer at Glacier National Park.

 Search efforts began on Tuesday morning, July 9, and are continuing by ground and air.