@Hellos: That wouldn't kill Jason. They'd turn their backs, turn back and he'd be gone and might actually appear in front of them some how (high speed travel? teleportation? hallucinogenic abilities?). Physical attacks don't really work on him. He's been getting decapitated, set on fire, jettisoned into space, sliced in half, ran over by cars, dismembered, and a variety of other things for decades and none of them kill him.
His only weakness is if he has killed a large number of your friends and only one or two of you are left, he may lose interest in pursuing you as targets if you can land a strong blow on him. That doesn't always work though. Sometimes he'll comeback for a sneak attack on you days or weeks later.