Coniston massacre
The Coniston massacre, which took place near the Coniston cattle station in the then Territory of Central Australia (now the Northern Territory) from 14 August to 18 October 1928, was the last known officially sanctioned massacre of Indigenous Australians and one of the last events of the Australian Frontier Wars. People of the Warlpiri, Anmatyerre, and Kaytetye groups were killed. The massacre occurred in revenge for the death of dingo hunter Frederick Brooks, killed by Aboriginal people in August 1928 at a place now known as "Yukurru", also known as Brooks Soak.
Sir Henry Wilson, 1st Baronet
However, this claim has been challenged. Any order to assassinate Wilson would have had to have been relayed to them by Rory O'Connor (then in charge of British IRA operations) and the last assassination attempt contrived against Wilson had been set to be executed in 1921, not 1922. Coogan has suggested that Reginald Dunne, who had the confidence of both Michael Collins and Rory O'Connor, undertook the shooting as a last-ditch effort to provoke the British Government into retaliating, thereby uniting both sides of the Nationalists. Hart believes the assassins "acted alone in the (grossly mistaken) belief that Wilson was responsible for Catholic deaths in Belfast". The killers had only decided to attack the previous evening, and even on the day Sullivan had been at work until 1pm; the killers had no getaway plan.