Electric shock

Today when I took Ozzy out for a walk in a wooded park, we came across a Malinois. He was off the lead and went for Ozzy. He tackled Ozzy into a submissive position and started biting him in the neck whilst growling furiously. Quite impressive. I remain calm in situations like these and walk on and call Ozzy to me. This usually diffuses the confrontation. Not this time. I managed to call Ozzy to me without showing any distress but by asserting control. The owner started sreaming at his dog and said "you'll get it in the neck, mate". This is exactly what happened. The poor dog was wearing an electric shock collar and his owner was so angry, he pushed the button for such a long time the dog started shaking and frothing at the mouth. This was obviously not enough for him. He took the lead and started beating his dog with the end with the buckle. The dog whelped. By this time Ozzy and I were at a safe distance. Luckily Ozzy is very sweet natured and trusts me so he was not affected by the scene. I did not think it was wise to make a comment to the man but I was upset for the poor dog and very angry with his owner. Poor Malinois, obviously in the wrong hands.