Police officer's head smashed on ground in 'sickening' attack by 6 people

Two Victoria police officers were rushed to the hospital after being attacked by six men and one woman. One officer needed emergency shoulder surgery. One of the officers has his head repeatedly slammed into the ground. They do not use their firearms because they would likely be the ones who get in trouble, even though in this situation it appears as though they should have shot someone to protect themselves. This happened in St. Kilda, Australia.