Christopher Alexander Falconer of Heathbell, N.S., was arrested Wednesday morning at the medium-security Dorchester Institution in New Brunswick, the RCMP and New Glasgow police told a news conference on Thursday.
RCMP Supt. Darrell Beaton said the arrest was the result of months of thorough investigation by both police forces into Amber Kirwan's death.
"We sincerely hope that the arrest will be a step forward in the healing process for Amber's family and indeed the entire community," said Beaton.
He wouldn't reveal specifics around the case or what led police to arrest Falconer.
"I can say that Christopher Falconer became a person of interest in the early stages of the investigation," Beaton said.
He said investigators believe that Falconer and Kirwan were strangers to one other.
"The investigation uncovered that there was no previous relationship and to the best of my knowledge they didn't know each other," said Beaton.
Kirwan was reported missing last October and her remains were found in a wooded farm property near New Glasgow about a month later. Police later ruled her death was a homicide.
She was last seen on a surveillance video leaving a pool hall last Oct. 9 and was believed to be walking to a convenience store to meet her boyfriend, who said she never arrived.
Falconer was granted full parole a year ago after serving 12 years for the murder of Robert LeBlanc of Pictou, N.S., in 1998.
Falconer was 15 at the time of the murder but stood trial as an adult. He pleaded guilty to second-degree murder in the strangulation of LeBlanc, a cab driver who was killed after picking up a fare on Jan. 2, 1998. RCMP found his body stuffed in the trunk of the cab.
In releasing Falconer on full parole, the National Parole Board said he had adjusted well to a halfway house after he had been granted day parole in May 2009 and was attending counselling.
"You have adopted a healthy lifestyle, are gainfully employed, and have good community support," the board's decision says.
"You now have a better understanding of your risk factors and what needs to be done to manage your social integration effectively. The board is quite confident that you will continue in the right direction while on a more liberal release considering your current situation and your participation in counselling."
Falconer's parole was revoked in February when he was questioned by police last October for his possible involvement in what the board described as a "serious offence." The board says police found a locking blade knife, marijuana and a .22-calibre magazine containing eight rounds in Falconer's possession.
He pleaded guilty to weapons and drug charges and was sentenced to four months in prison.
New Glasgow police Chief Delaney Chisholm said Kirwan's death was a senseless tragedy that affected the local community.
"It shattered many people's sense of safety and security," said Chisholm.
"I hope today's announcement of an arrest and charges will bring a sense of release to the people of New Glasgow and the surrounding community."
Falconer made a brief appearance Thursday morning in Pictou provincial court, where his case was adjourned until June 18.
Police said they also arrested a woman Wednesday but later released her without laying charges.
Beaton said the woman's arrest was not crucial in the laying of charges against Falconer.
"Whether or not we arrested this individual and the manner in which that aspect of the investigation unfolded had no bearing on whether or not we were going to charge Mr. Falconer."
Beaton said police didn't expect to lay any additional charges.