Police hunting a gunman who killed a ranger in Mount Rainier National Park found a body on Monday, a spokeswoman said.

It was not immediately confirmed that the corpse was that of suspected gunman Benjamin Colton Barnes, 24, who fled into the forest after the New Year's Day shooting in the snow-covered park.

"A suspect in the area of Narada Falls has been found. His identification is unverified at this time. Tactical teams are making their way to the subject to determine his identity and status," spokeswoman Lee Snook told AFP.

Some 200 police and officials had resumed a massive manhunt at first light, searching for the snow-shrouded park for the "armed and dangerous" suspect, identified by local media.

Barnes had served in Iraq but suffered from post-traumatic stress disorder, according to the Seattle Times, which linked him to another shooting earlier Sunday in which four people were injured.