Media has provided a few more details. The killers were two brothers and a sister in law. They had shot two police and whilst they were down walked up to them and shot them again. The killers also murdered a neighbour. It is alleged they were believers in a yet to be identified conspiracy group. Special Police later shot the three of them in an exchange of gun fire, I assume they were police snipers.

 

Six dead after Queensland police ambush (msn.com)