According to the Calgary Herald, police arrested two men this weekend on charges of damaging vehicles and possession and dangerous use of a weapon.
A bullet was fired Saturday in the direction of a trucker delivering cargo from the port. The man wasn't injured, but the bullet shattered part of his vehicle's windshield.
Another man was arrested and charged with making threats against the owner of a trucking company.
The three men will appear in court early next week.
The protesting truckers want to join a small truckers union and to reach collective agreements on wages and working conditions with the companies. They have targeted their protest against about 40 trucking companies who refuse to recognize their right to collectively bargain.