THE man who bashed an armed guard outside Victoria's Parliament House, stole his gun and shot himself dead was known to police.

But Assistant Commissioner Andrew Crisp said he would not go into the details of the man's past as they probe for a motive of the violent attack.

He said police are now examining what could have prompted such a violent incident.

Police say the man was talking to the Protective Services officer outside Parliament last night, when he hit him in the head with a hammer and stole his handgun.

The man's body was found a short time later in a nearby park.

The PSO, believed to be in his 40s, is recovering in hospital after overnight surgery.

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