Former Marine James Popkowski, 37, was fatally wounded in the midmorning confrontation near the Department of Veterans Affairs Medical Center in an area of the city known as Togus.

Mills said it was not clear what triggered the confrontation in woods near the hospital. She also said it wasn't clear whether the officers were fired upon by Popkowski, who lived about 150 miles away in the town of Medway.

But "From the preliminary investigation, it appears to be defense of themselves and defense of third parties," Mills said.

The attorney general's office said Popkowski was a former Marine, but had no further information on when or where he served. The office said VA police officer Thomas Park and state game warden Sgt. Ron Dunham used deadly force against the man. A third officer, game warden Joey Lefebrve, was involved but did not use deadly force. All three were placed on administrative leave with pay pending the outcome of the investigation, officials said.

Hospital spokesman Jim Doherty said police for the VA hospital, which has its own federally licensed force, were summoned after a couple of employees heard gunshots in nearby woods. When police confronted the man, VA employees and patients were told to stay inside the medical campus buildings.

Doherty confirmed that Popkowski had received health care at the VA. But Doherty said he was barred by confidentiality protections from giving the dates or reasons for the treatment.

A 2003 published report said a benefit bone-marrow drive was to be held for Popkowski, then a lst lieutenant in the Marine Corps who had been diagnosed with a rare and aggressive cancer.

Neighbors gave differing accounts of whether people hunt in the woods surrounding the hospital. The area where the shooting took place was marked with a "no trespassing" sign and identified as federal property.

Paul Stevens of Belgrade, who was visiting his uncle who lives near the woods, said he saw what happened.

Stevens, who said he was a National Rifle Association shooting instructor, said officers fired on a man armed with what looked like a rifle. About eight shots were fired and the man fell to the ground, he said. Stevens said he did not see any aggressive action by Popkowski before he was shot.

"It's a sad thing," said Glenwood Shaw, Stevens' uncle. "I just think it's awful for someone to lose their life that like."

Popkowski was apparently the owner of a Toyota pickup with a veteran's license plate that was parked about 40 to 50 feet off the road, Shaw said. Shaw said he'd seen the pickup parked in the area previously.

Janice Currie, who lived across the street from Popkowski's family in Medway, said Popkowski joined the Marines after high school and planned to make a career of it, but his military career was cut short by a rare form of cancer.

Currie said Popkowski never recovered from the cancer but remained upbeat during treatment. He had three Alaskan huskies that he often took with him in his pickup truck, she said.

"He was a very nice guy," she said. "This totally took me by surprise because that's just not him."

By law, the attorney general's office in Maine investigates whenever officers use lethal force.