Police investigators in Maine, Boston and Canada gathered information Monday in hopes of uncovering a 20-year-old Canadian dishwasher’s motive for gunning down two convicted sex offenders in their rural Maine homes early Easter morning.

Stephen A. Marshall, 20, gained access to information about his victims, along with the names of 32 others on the state’s online sex offender registry, officials said Monday.

Marshall took his life Sunday night after leaving Bangor for Boston, where he was cornered on a bus by Boston transit police.

The North Sydney, Nova Scotia, man shot and killed Joseph L. Gray, 57, of Milo at about 3 a.m. Sunday in Gray’s living room.

Five hours later, he shot and killed William Elliott, 24, in Elliott’s mobile home in Corinth.

Both men died of multiple gunshot wounds, Stephen McCausland, spokesman for the Maine Department of Public Safety, said Monday.

Investigators were not certain Monday of the relationship – if there was one – between Marshall and the two victims, McCausland said.

“This is a very complicated case, and we’re trying to seek as many answers as we can, but we still have a lot questions that we don’t have answers to,” he said. “We’re working with our counterparts in Boston, and Canadian authorities are conducting a whole host of interviews. We have no background on Marshall at all.”

Marshall was visiting his father, Ralph Marshall, in Houlton, when late Saturday or early Sunday morning he slipped out a window, taking a rifle and two handguns, along with his father’s silver 2002 Toyota pickup, according to Houlton police. He had crossed the border into Maine on Thursday to make the visit.

A father grieves

Ralph Marshall, who appeared Monday red-faced and teary-eyed, said he did not want to comment on his son or the investigation.

The white-haired father stood Monday on his porch, then walked down into his dooryard to speak to a handful of print and television reporters.

Marshall, an economic developer with the Houlton Band of Maliseets, said initial reports claiming it was the first time he and his son had ever met were untrue.

“We had a very strong relationship,” he said, choking back sobs. “He came to visit me infrequently, but it’s a long trip from Nova Scotia.”

The elder Marshall said his son was a dual citizen of the United States and Canada, and had a sister in Nova Scotia. The family reportedly will make funeral arrangements in the next few days.

Ralph Marshall denied rumors that he himself was a victim of sexual abuse, and said he did not believe his son had been sexually abused.

“It’s just unbelievable,” he said repeatedly, swallowing back tears.

He did not want to comment on what might have motivated his son to commit the crime, and said that his son had been acting normally during the visit.

Details of the investigation

When Stephen Marshall shot himself on a bus in Boston at about 7:30 p.m. Sunday, he had with him a laptop computer and two handguns, according to David Procopio, spokesman for the Suffolk County (Mass.) District Attorney’s Office. Those items will be turned over to Maine investigators, he said Sunday.

McCausland said Monday that police believe the .45-caliber gun Marshall turned on himself is the gun he used to shoot both victims.

Because Marshall may have used Maine’s sex offender Web site to target his victims, it was taken offline Sunday as a precaution and so a forensic investigator could find out what information Marshall might have taken from the site.

McCausland said Monday that he had only partial information from the analysis of the Web site by members of the Computer Crimes Task Force. He expected an examination of Marshall’s laptop would reveal more information.

The computer was not returned to Maine on Sunday, he said.

Maine’s sex offender Web site, which has the names of more than 2,200 sex offenders, contains such information as the offender’s name, address, date of birth, identifying characteristics and place of employment, as well as a photograph.

The Web site was back online early Monday afternoon.

“The Web site is back on. It is there by law,” McCausland said. “The reason why the information is available to the public is well-documented.” The sex offender registry, he said, is the most popular page on the state’s Web site.

Law enforcement officials worked Monday to track Marshall’s movements on Sunday, but details remained sketchy 24 hours after he turned one of his father’s guns on himself.

Houlton Police Chief Daniel Soucy said Monday that his department first became aware of the crimes when contacted by Maine State Police early Sunday afternoon. Officer Troy Fitzpatrick and Officer Daniel Norton went to Ralph Marshall’s Court Street address.

Soucy said that the father and son were planning to spend some time together and intended to go target shooting.

The father told police he believed that his son had taken his vehicle and also reported that his weapons were missing.

Ralph Marshall was legally in possession of the guns, according to Soucy, and Houlton police had no prior contact with him or his son.

The chief said that the elder Marshall did not report the vehicle as stolen because he believed that his son might have taken it to go target-practice.

Two victims gunned down

The Penobscot Regional Communications Center received a report of a shooting at the Gray residence in Milo at about 3:14 a.m. Sunday.

Gray’s wife, Janice Gray, 55, was asleep in her bedroom when she was awakened abruptly by men’s voices, a Boston newspaper reported Monday. When she went to investigate, the woman saw her husband shot and killed in front of the TV, a family associate who asked not to be identified told the newspaper.

“By the time she got to the living room he had been shot,” the associate said.

Five hours later, a similar call came in from Corinth.

Elliott’s girlfriend, who reportedly witnessed the Corinth shooting, gave detectives a license plate number and a description of the truck in which the gunman fled the scene. Bangor police found a 2002 Toyota Tacoma pickup bearing that license plate at about 1 p.m. Sunday behind Sawyer Arena in Hayford Park in Bangor.

“The shell casings that we found here the crime lab has tentatively matched to those casings that were in Corinth,” Detective Sgt. Stephen Pickering of the Maine State Police said Monday, sitting in a cruiser in the Milo victim’s driveway.

The rifle was found in the pickup truck, he said.

McCausland said Monday that he had no further information about what had been recovered from the pickup.

Truck stops at Davis farm

A truck matching the description of Marshall’s vehicle was spotted about 9 a.m. Sunday at the Kenduskeag dairy farm of Penobscot County Commissioner Tom Davis.

Davis speculated Monday that Marshall drove onto the farm off Route 15 to avoid the Penobscot County sheriff’s cruisers that were headed north toward Corinth.

“He stopped in two different locations on the farm,” Davis said Monday in a phone interview. “It pulled into one of my driveways and apparently saw that it was not a through road.

“He tried to go across a field, but got stuck in the mud, spinning his tires, throwing mud onto the truck.

“He got it unstuck,” Davis continued, “then drove a short distance to the area where the silo and commodity sheds are. When one of my workers approached the truck, he took off and got on Route 15 headed toward Bangor.”

Davis said that 10 to 15 minutes later one of his workers heard on his scanner that police were searching for a pickup that looked like the one that was seen at the farm. The worker told Davis, and the county commissioner called Penobscot County Regional Dispatch between 9:30 and 10 a.m.

State police came to the farm about 10:30 a.m. and took impressions of the tire tracks, but did not find anything the driver might have discarded, Davis said.

“He wasn’t here but three or four minutes,” he said. “I think he just drove in here to get away from the sheriff’s deputies when he heard the sirens.”

McCausland said Monday afternoon that it had not been determined whether the tire tracks found at the farm matched Marshall’s truck.

Victims’ crimes dissimilar

Although the victims lived less than 20 miles apart, the crimes that led to their listings as sex offenders had few similarities.

Gray was convicted in Bristol County, Mass., in 1991 for indecent assault and battery on a child under the age of 14 and the rape of a child. He lived in Mansfield, Mass., in the early 1990s, and still has relatives in the area, a Boston newspaper reported Monday.

Elliott was convicted in 2002 in 3rd District Court in Newport of sexual abuse of a minor and sentenced to four months in jail. As a result of that misdemeanor conviction, he was ordered to register as a sex offender for 10 years.

The Corinth victim’s father, Wayne Elliott, 61, of Charleston, told the Bangor Daily News on Sunday that the victim in that incident was his son’s underage girlfriend.

McCausland said Monday that he did not know the details of the crime that led to William Elliott’s being listed on the sex offender Web site.

The killings in rural Maine have attracted worldwide media attention. “Primer Impacto,” a Spanish-language television program broadcast on the Univision Network, aired the story.

Reporters from Boston and the Canadian Maritimes converged on the area to report on the multiple killings.