Warning - the whole video is posted as a reply on this Twitter post.

Must of hacked at his neck twenty some times while his wife and son are trying to stop him. There are bystanders on their cell phones watching behind their cars.

Make sure you and your loved ones know how to defend and disarm someone. Even if you get stabbed, make sure its your hands or arms that take a hit, then disarm and throw the weapon out of reach. Please don't just take a class and think it will stick for life, you have to practice this stuff.