Legal Jurisdiction

John is standing on the northern bank of the Macintyre River. His mortal enemy, Bob, is standing on the southern bank. This means John is standing in Queensland and Bob is standing in New South Wales. John takes out a gun and shoots Bob. Bob falls into the water and then dies in the middle of the river, directly on the border of QLD & NSW. What state has jurisdiction? Elements of the offence happened in two different states at the same time but the cause of death was drowning however the shooting led to the death