Inmate deaths at federal penitentiaries in Nova Scotia are the highest they've been in at least five years, according to numbers obtained by CBC News.

It's a trend Canada's prison watchdog calls "disturbing."

So far this year, there have been three deaths in the province's federal correction facilities. One was at the Springhill Institution and two were at the Nova Institution for Women.

Between 2010 and 2014, there were no deaths at the Nova Institution for Women. At the Springhill Institution, there was one death each in 2011, 2012 and 2014. There were no deaths at that institution in 2010 and 2013.

The latest inmate death at the Springhill Institution in Nova Scotia happened over the weekend, prison officials said Monday. (CBC)

Howard Sapers, the Correctional Investigator of Canada, say this year's three deaths are "raising some red flags."

"Really disturbing is two of those deaths involved women who died at the Nova Correctional Institute and last year we had no women die in custody," he said.

"It speaks very much to both the nature of care in custody in Canada but also who it is that's going into federal penitentiaries."

On Saturday, Terrance Matchett, a New Brunswick man serving at the Springhill Institution, was found unresponsive in his cell. Prison officials have not disclosed how he died.

Last month, Camille Strickland-Murphy killed herself at the Nova Institution for Women. A Newfoundland woman, Veronica Park, died while in custody at the women's prison in April.

Last year, there were 67 deaths in federal correctional institutions across Canada. In the first four months of 2015, there were 31, said Sapers.

​"We're seeing some trends early in the year which are disturbing," he said.

Reviews launched

The office of the Correctional Investigator is reviewing all three cases in Nova Scotia and could choose to launch a deeper investigation, said Sapers.

"This could be that this a terrible series of coincidences. It could be this is an anomaly. It could also be telling us about some other issues," he said.

"It could be reflected of staffing issues, it could be reflected of training issues, it could be reflected of the characteristics of the offenders who are coming into an institution or a combination of all of those things."

Two inmates at the Nova Institution for Women have died so far this year. There hasn't been a death there since 2010. (CBC)

Sapers says when his office does investigate, they often find "troubling" patterns when it comes to access to health care, psychological assessments, quality of first-aid response and compliance around restraint.

"It heightens our concern about the ability of Correctional Service Canada to learn from previous mistakes," he said.

Atlantic institutions are not as crowded as other facilities across Canada, Sapers said. Even so, last year there were seven deaths at Atlantic penitentiaries — and five so far this year.

Sapers's office is still waiting for autopsy results for three of this year's deaths.

"We suspect suicide in two of the three but no determination have been made," he said.

"There does seem to be something going on and it's too early to tell if that's an anomaly or if it's an indication of a larger trend that might expose some other problems. I don't want to inappropriately target Atlantic Canada as being particularly problematic, but the numbers do have our attention."

'Duty of care'

While there's no quick answer as to why more inmates are dying in care, Sapers said his office is seeing an increase in the number of mentally ill patients being sent to custody.

"They are disproportionately involved in self-injury incidents," he said.

Sapers also notes some deaths are natural. Many inmates have chronic diseases and the inmate population, as a whole, is aging. Contraband also plays a role in some deaths, he said.

"The CSC has to figure out strategies to deal with all of that. They do have a duty of care," he said.

​In the past, the office of the Correctional Investigator has made recommendations on enhanced training and a prohibition on segregation for people with a history of self-harm.

They've also recommended correctional facilities should be retrofitted to eliminate what are known as "suspension points" — parts of an inmate's cell where a ligature could be hung.

"Those recommendations have not yet been adopted," Sapers said.