Harper says everyone should encourage veterans in need to reach out to the support and systems that are there to help.
The prime minister's comments came hours after the Defence Department confirmed the military police at CFB Valcartier in Quebec are investigating the death Tuesday of Master Cpl. Sylvain Lelievre, from the 3rd battalion of the Royal 22e Regiment.
Lelievre is the fourth soldier believed to have committed suicide since last week.
Lelievre joined the Canadian Forces in June 1985 and was deployed to Bosnia between 2001 and 2002, and again in 2004. He also served in Kandahar from 2010 to 2011.
"The loss of any soldier is devastating to the military community and our condolences go out to his family and friends," spokesman Capt. Denny Brown said Wednesday in an email.
"As the death took place on the base, it is now under military police investigation. As such, it is inappropriate for us to comment on the investigation."
The escalating struggle of soldiers has been resonating across the country since word of the suicides began emerging.
The deaths include a senior non-commissioned officer at Canadian Forces Base Petawawa, northwest of Ottawa, as well as two other soldiers in Western Canada.
Veterans advocates say the number of apparent suicides within the military in recent days may only hint at the magnitude of the problem. For every death by suicide, they warn, as many as a dozen others may have unsuccessfully sought the same fate.
In a video message to military members on Wednesday night, Gen. Tom Lawson, the chief of defence staff urged them to reach out for help when battling mental issues.
"Just as you would expect to be helped by your colleagues on the battlefield if you were physically injured," said Lawson, "your brothers and sisters in arms are with you in the fight against mental illness."
"Although suicide is an international public health concern," added Lawson, "for an organization like ours built on leadership, built on camaraderie and built on strength, it hits us especially hard."
”In order for us to help each other, it’s essential that all military personnel like all Canadians recognize mental health issues as they develop.”
Veterans ombudsman Guy Parent said spouses of veterans suffering from post-traumatic stress disorder need to know how to spot the warning signs. He also says greater financial stability is needed for veterans.
"Obviously, there's been a few in the last few days, and that's unfortunate," Parent said after appearing at a Senate committee.
"Again, it's not a matter of numbers. It has nothing to do with numbers. It has to do with what got the people in those situations to make that decision, and if we can facilitate their voyage to transition it would be much easier for everybody."
A sign of how it is impacting even top-level former military personnel came Tuesday when Liberal Sen. Romeo Dallaire fell asleep at the wheel of his car and crashed into a traffic barrier on Parliament Hill.
The retired general cited the news last week of three Canadian soldiers killing themselves, as well as the coming 20th anniversary of the Rwanda genocide, as reasons he has been unable to sleep, even with medication.
Former defence minister Peter MacKay said he is troubled by reports of another veteran of the Afghanistan war taking his own life.
MacKay, now minister of justice after years in the defence portfolio, says the news is heart-wrenching.
"It's absolutely heartbreaking and troubling in the extreme that anyone, soldiers in particular, find themselves in a position that they see no hope and take their own lives," MacKay said Wednesday on his way into the weekly Conservative caucus meeting in Ottawa.
Defence Minister Rob Nicholson this week asked those who are struggling to seek help.
The Canadian Forces Member Assistance Program has a confidential 24/7 toll-free telephone advisory and referral service for all military personnel and their families: 1-800-268-7708.
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