The Edmonton Police Commission is looking into how city police helps officers cope following traumatic investigations such as the Loblaw warehouse stabbings.

"They deal with the operations, they deal with the safety of the people there," said Staff Sgt. Tom Pallas. "Then it's not until everyone's safety is put away, and bad guy is locked up, if that's the case, that all of a sudden then the mental piece starts settling in."

Studies show between three and 10 per cent of any police department suffers from post-traumatic stress.

While there are only six documented cases of PTSD in the EPS since 2008, that may not be the whole story, said Dr. Chris Diachuk, in charge of EPS employee health.

"The number of people with full blown PTSD is a relatively small number," he said. "However the people impacted by traumatic events is quite a bit larger." 

First responders to crime or accident scenes, such as police, are most vulnerable to PTSD, he said.