No, don’t do that. Answer my question, He was fleeing, WHY? And if YOU don’t have a reasonable answer then I would suspect the cop didn’t either, he could only surmise the worst, had only a split second to think about WHY a perp grabbed his arm, and was taking off.
OK assume for a minute he was fleeing. So what? The man had not shown he was armed or a threat to anyone. Call it in, go to your car and pursue. Why the need to immediately shoot him in the head?