Investigators publicly affirmed Wednesday (Nov. 16) that they believe James Dale Ritchie killed at least one of the five victims in a spate of summertime homicides in Anchorage linked to a single uncommon gun.

That gun, a Colt Python .357, was found on 40-year-old Ritchie Saturday (Nov. 12), after police say he shot Anchorage Police Department officer Arn Salao in an early-morning encounter. Ritchie was killed at the scene when Salao and another officer returned fire, according to APD.

In a Facebook live video posted Wednesday, APD Capt. Bill Miller and Lt. John McKinnon spoke to an online audience in a wide-ranging conversation that unveiled fresh details in what had previously been tightly controlled investigations.

They cautioned it's still too early to say if Ritchie killed anyone other than Treyveonkindell Thompson, who was found dead on an East Anchorage street on July 29.

Thompson had been shot with a Colt Python by a man estimated at about 6 feet, 3 inches tall and wearing a camouflage jacket, based on surveillance footage captured in the area of the shooting, according to an investigative timeline released by police. Several witness accounts were also able to generate a composite sketch of a possible suspect in that case.

Police said Ritchie, who was 6 feet, 4 inches tall, was wearing a camouflage jacket — similar to the one in the Thompson case — when he was killed early Saturday in the officer-involved shootout.

"We have enough evidence to support that Ritchie killed Treyveon Thompson," McKinnon said Wednesday. "That case will become closed."

More investigation is needed to determine whether Ritchie may have been at the other crime scenes. Those include the double homicide of Brianna Foisy, 20, and Jason Netter Sr., 41, on a Ship Creek bike path July 3 and the killings of Bryant "Brie" DeHusson, 25, and Kevin Turner, 34, at Valley of the Moon Park on Aug. 28.

Viewers contributed questions and comments during Wednesday's live chat, but the 45-minute conversation was steered by APD's communications director, Jennifer Castro.

The detective commanders began the broadcast by describing the dearth of evidence at the scene where the bodies of Foisy and Netter were found in early July.

"They had nothing around them. They were just on the trail," McKinnon said.

Police collected video from the many business surveillance cameras in the area — a terabyte of video that detectives spent "several hundred hours" watching frame by frame. They found no image of a suspect or suspects.

When ballistic analysis came back, police knew the bullets had been fired from a Colt Python — a relatively rare gun no longer on the market.

"That was probably our most important clue from the first investigation," Miller said.

After the killing of Thompson on July 29, police determined the gun used was the same Colt Python from the Post Road shootings.

But they decided not to tell the public the homicides appeared to have a link.

The FBI advised them not to, said Miller. The gun was "absolutely the only clue we had that could tie the cases together."

Police were concerned a suspect showing a propensity to "commit serial crimes" would follow news developments and might toss the gun but continue killing, Miller said.

"It was our fear that he was going to get rid of this weapon and would disappear to start committing more homicides in a way we couldn't link," he said.

After Ritchie's death, police confirmed he was monitoring news reports on the homicides, McKinnon said.

The decision to keep the evidence under wraps wasn't made lightly, they said.

"What would it have contributed to public safety in general to know there was a Colt Python involved in all these cases?" McKinnon said. "We couldn't think of any proactive things people would do for their safety."

Then, a month later, bullets from the same revolver killed two more people.

On Wednesday for the first time, police officials offered a detailed explanation of what happened in Valley of the Moon Park early on the morning of Aug. 28:

One of the victims, Kevin Turner, was sitting in a picnic pavilion "probably minding his own business" when he was attacked, McKinnon said. He was shot once.

The second victim, Bryant "Brie" DeHusson, was traveling down the trail on a bicycle and was "likely shot from a distance," McKinnon said.

The bodies were found minutes after the killings took place, he said.

Police were able to capture the silhouette of a figure from a camera on Arctic Boulevard. The image wasn't clear enough to reveal whether it was a man or a woman, but the person's timing walking past the camera toward the park and then returning in the other direction "matched our time frame."

Police also talked about a profile of the sort of person they believed the killer to be. They did not discuss potential motive in any of the cases.

Behavioral analysts suggested the person was "someone kind of on the fringes," Miller said.

It's not clear what kind of life James Ritchie was living. He'd grown up in Anchorage before leaving the state for a time. He returned to Anchorage in February of this year, police said Tuesday.

The last place Ritchie lived was East Anchorage. Miller and McKinnon did not elaborate on how long he lived there. It wasn't clear how Ritchie filled his days since moving back to Alaska.

"We're trying to find out what his movement has been around the United States and in Alaska through the last few years," Miller said.

He was in contact with his family, McKinnon said.

Detectives are also trying to find out how Ritchie, a felon, acquired the gun.

The Colt Python was purchased in 1971 by someone in Anchorage. The original owner is still alive, and police plan to talk to the person to find out more about the gun's chain of ownership.

Ritchie was alone and walking down Fifth Avenue when officer Arn Salao encountered him early Saturday morning. Salao was responding to a report of a cab passenger who skipped out on a fare, and the run-in with Ritchie happened entirely by chance, Miller said. McKinnon said he believed there might have been more killings had Ritchie not been shot to death in the encounter with police.