TORONTO - Court is hearing today about the havoc the driver of a stolen snowplow continued to wreak around Toronto after hitting and killing a police officer.

Richard Kachkar, 46, is on trial in the death of Sgt. Ryan Russell, 35, and he has pleaded not guilty to first-degree murder and dangerous driving.

The judge has told the jury that there will be no dispute that Kachkar was the person driving the plow, rather the case will centre around his mental state.

Court has heard that Kachkar drove in opposite lanes, through red lights and into other vehicles around Toronto for about an hour before and after killing Russell.

Anthony Muhitch testified today that he was driving to his job as a teacher on the morning of Jan. 12, 2011, when he saw a truck with a plow on the front suddenly accelerate into an intersection and broadside the car in front of him.

Muhitch says the impact essentially took the car onto its hood and propelled it, spinning, into his own car.