OTTAWA : Canada's military was investigating Wednesday the apparent suicide of a fourth soldier in a week, all of them after returning from tours in Afghanistan. Master Corporal Sylvain Lelievre was found dead in his home in Chandler, Quebec on Monday. He was 46.

His death comes after three others across Canada were determined to be the result of suicide, and possibly linked to post-traumatic stress. Officials would not comment specifically on the recent spate of suicides.  But Defence Minister Rob Nicholson implored any soldier who is struggling to seek help.

"We all have a role to play in reaching out to those who are hurting and encourage them to get help," Nicholson said in a statement.  "I want to remind those who may be going through difficult times that you are not alone and there is support available to get you through this."

Last Wednesday, the body of Warrant Officer Michael McNeil was found at a military base in Petawawa, north of the capital Ottawa.

A day earlier, Master Corporal William Elliott died at his home near Canadian Forces Base Shilo in southwestern Manitoba.

And Master Bombardier Travis Halmrast died in a Lethbridge, Alberta hospital after a suicide attempt.

Canada's longest-running combat mission officially ended in July 2011 -- after joining NATO's coalition in Afghanistan to overthrow the Taliban a decade earlier -- with the handover of security duties in Kandahar province to US and Afghan troops.

Canadian forces have since been training Afghan army and police in and near Kabul. The last military trainers are scheduled to pull out of Afghanistan in March.

Canada's public broadcaster CBC cited government figures that show 22 Canadian soldiers committed suicide in 2011, and 13 took their own lives in 2012.