The arrest of 41-year-old Sean Butler of Kitchener saw an officer bitten by a pit bull and the dog shot and killed Sunday night.

Waterloo Regional Police pulled over a car to execute a warrant around 7:30 p.m. at Daimler Drive and Briarmeadow Place in Kitchener.

Sean Safa is the lawyer representing Butler and says his client was arrested at gunpoint.

"When they were effecting the arrest when they had Mr. Butler down, the dog had jumped out of the car…and the dog bit the officer and at one point the dog had let go but then had come back at the officer and the officer had to shoot the dog."

Spencer Miller was in a nearby home with some friends, and says they heard three gunshots.

"All I saw was an officer lying down on the ground, we didn't know it was an officer even at that point, but we saw someone lying on the ground and a dead dog lying on the sidewalk."

Butler was arrested on four counts of sexual assault, human trafficking, forcible confinement and uttering threats.

Police say a woman reported she was taken to a Peter Street apartment and violently assaulted.

According to Safa many people think human trafficking is just about buying and selling people, but "If you trade a person in return for drugs or money they call that trafficking."

He says is still waiting for full disclosure of the charges against his client.

Butler made a brief court appearance Monday morning and is being held in custody. He will make a video court appearance on Nov. 2.