The convention we used was a freeze-frame to show fear. We had two people standing up using a dominant stance, holding a bow and arrow to show power. The third person was crouching down on the ground, holding her hands to her face to show how scared she was. We held the freeze frame for more than three seconds so the audience we able to observe everything. This was also done to make the audience feel sad for the person being attacked.
E.g of freeze frames: