Chief Commissioner Graham Ashton described the challenge of dealing with mental health issues among police as "one of the most important issues I have to address during my time".

There had already been at least four officers who had taken their lives this year, Mr Ashton told the ABC.

It is believed one of the officers who died was from Echuca, but did not die at the station. Details about the second death are not yet known. 

In October, The Age reported that an officer had taken their own life, soon after they were deemed fit to carry a service firearm, despite suffering from mental illness.

It was also reported that a senior police officer who was charged with murder had suffered mental health issues for almost a decade before he allegedly shot and killed a man during a routine intercept in Windsor.

Senior Constable Tim Baker, 44, allegedly shot Mr Micetic three times in the chest during the intercept in 2013, and claimed he acted in self-defence. 

He is believed to have had an extensive history of psychiatric problems, which has raised further concerns about Victoria Police's handling of mental illness and its policies surrounding access to firearms.

Mr Baker took extended leave on several occasions because of his illness, and was only allowed to resume work after approval from a Victoria Police psychiatrist.

But less than a year before the shooting, it is believed Mr Baker was involved in a serious altercation with another officer that should have set off alarms, according to colleagues of the accused man.

The Coroner is also set to investigate the death of a Sergeant who took his own life last June.

Earlier this week, Victoria's Police and Corrections Minister Wade Noonan announced he was taking extended leave citing the toll that exposure to "unspeakable crimes and traumatic events" had taken on his mental health.

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