Police in Halifax are treating the death of an 81-year-old man at a continuing care facility as a homicide.

But they say a 71-year-old who was involved in an alleged altercation with the elderly victim will not be charged because he has a cognitive impairment.

“This is a tight-knit community and this is a loss that will be felt throughout this home,” said Shannex spokesperson Heather Hanson.

Police say the man, who they have not identified, died Saturday night and police were called to the Parkstone Enhanced Care facility the following morning.

They say it's believed the man may have been pushed by a fellow resident earlier in the week, causing him to fall down and subsequently pass away.

Both were residents inside a secure area for dementia patients.The medical examiner's office ruled the death a homicide following an autopsy.

Officials with the facility say physicians on site checked the man immediately after the fall and there were no apparent injuries. Two days later when the man's health began to decline, a critical incident report was filed with the Department of Health.

“We’ve been working with [the Department of Health], the medical examiner's office and Halifax police and, very importantly, we've been working with the families,” said Hanson.

There have been three incidents in the last five years where seniors in dementia units have died after altercations with other residents at a Shannex facility in Halifax.

The previous incidents involved two women in their 90s.

“Hopefully whenever things like this happen, the appropriate people examine what’s happened and see if anything else could be done in the future,” said Bill Vangorder of the Canadian Association of Retired Persons.

Vangorder says it’s often hard to prevent the unexpected.

“The only way of totally preventing it would be total isolation, and you can’t do that,” he said.

Police say they have closed the case after consulting with the Public Prosecution Service and deciding not to lay charges because the suspect is not criminally responsible due to a mental impairment.

If deemed necessary, the province will make specific recommendations to Parkstone officials.

With files from the Canadian Press and CTV Atlantic’s Kelland Sundahl.