An online video that appears to show a U.S. Marine flinging a puppy from the top of a steep hillside in Iraq continued to generate revulsion and outrage yesterday.

Marine Corps Base Hawai'i is investigating the actions because the video may have involved a Hawai'i Marine with the 1st Battalion, 3rd Marine Regiment. The unit returned from Iraq in October.

It remains to be determined whether the video is genuine or a hoax.

"I understand people's outrage," said Maj. Chris Perrine, a spokesman at the Kane'ohe Bay base. "I think every Marine is outraged by the video, and what I would do is encourage people to support our constitutional process and treat people as innocent till proven guilty and let the process run its course."

Thousands have viewed the 17-second video at www.YouTube.com. By last night, 156 people had posted comments - most of them directing extreme anger at the Marine in the video — on a story yesterday in The Advertiser.

Retired Hawai'i Air National Guard Maj. Gen. Albert "Putt" Richards said if the video proves to be valid, one or more Marines "should not be in uniform due to a severe personality disorder."

"If it is a contrived video, I question the stability of the minds that put it together," Richards said, adding that if he were their immediate commander, he would order a psychiatric evaluation.

The Humane Society of the United States wrote a letter to Defense Secretary Robert Gates yesterday noting what appears to be "a U.S. Marine tossing a yelping puppy over a precipice" in the video.

"We understand that the Marine in the videotape is identifiable, and we therefore expect the Department of Defense to investigate and take swift and appropriate disciplinary action," the letter said.

A Marine in the video identifies the man tossing what appears to be a black and white puppy as "Motari."

The Kane'ohe Bay base previously said a Lance Cpl. David Motari is with the 1st Battalion, 3rd Marine Regiment, but officials said they couldn't confirm Motari was in the video.

"He's here," Perrine said yesterday. "I don't know what he's doing on an hourly basis, but he is here."

As part of the investigation, the Marines will attempt to determine if the video is a hoax or the puppy already was dead.

Ashley Maynard, a psychologist and faculty member at the University of Hawai'i, said the visceral reaction demonstrated by so many to the video may be due in part to people being more accustomed to seeing violence against people in war, while puppies are seen as pets.

"So in the context of war, we may be appalled at some of the things that are happening, but we can also justify violence to humans as being something that is part of the war," Maynard said. "But an innocent little puppy is really a bystander to all of this."

Reach William Cole at wcole@honoluluadvertiser.com.