US authorities find body of missing Australian soldier Paul McKay

Police have found the body of an Australian soldier who had been missing in the United States for more than two weeks.

Police have found the body of an Australian soldier who had been missing in the United States for more than two weeks.

Captain Paul McKay disappeared on New Year's Eve after catching a bus to a remote town near the Canadian border and walking into the Adirondack mountains in freezing conditions.

His body was found around 150 metres from the trail at the top of Mount Scarface, near Lake Placid in upstate New York, about 11:00am local time on Wednesday.

Captain McKay's body, which was found only covered in a blanket, was airlifted by helicopter from the mountain.

Police say they have not discovered any signs of foul play.

"On January 15, 2014, New York State Forest Rangers located the body of a man who is tentatively being identified as missing Australian soldier ... Paul J McKay," a police statement said.

"The body was located near the summit of Scarface Mountain in the town of North Elba."

The Australian Defence Force (ADF) has confirmed the body is believed to be that of Captain McKay.

An ADF spokesperson says Captain McKay's family "has been notified of this development and Defence is continuing to provide them with welfare support".

"Defence will not provide any further personal or service details relating to Captain McKay at this time," the spokesperson said.

"Defence requests that media respect the family’s wishes for privacy."

An autopsy will be performed on Thursday (local time) to determine the cause of death.

Police chief Bruce Nason told local paper the Adirondack Daily Enterprise that Captain McKay's Australian family has been notified.

The 17-day search had involved dozens of volunteer searchers, rangers, dogs and a helicopter.

Captain McKay's father raised the alarm after he received an email in which his son said he was giving him all his property and possessions.

Captain McKay had never been to the US before and was not known to have any contacts there.

He had struggled emotionally with a post-traumatic stress disorder since returning from Afghanistan in 2011.

When Captain McKay checked out of his hotel in Saranac Lake and walked into the woods, it was just before the polar vortex hit.

The wind sent temperatures down to minus 30 degrees Celsius for days.

He left behind personal items after checking out of his hotel - including his camera and clothes.