During the Kelly outbreak, police watch parties monitored houses belonging to relatives of the gang, including that of Byrne's mother in the Woolshed Valley, near Beechworth. The police used the house of her neighbour, former Greta mob member and lifelong friend of Byrne, Aaron Sherritt, as a base of operations, sleeping in it during the day and keeping watch from nearby caves at night. Sherritt accepted police payments for camping with the watch parties and for providing information on the bushrangers' activities. While many policemen suspected him of being a double agent for the gang, a detective, Michael Ward, planned to bring the bushrangers out of hiding by spreading rumours that Sherritt's true loyalties lay with the police. Convinced that he was a traitor, the gang decided to murder Sherritt as part of their own plan, one that they boasted would "astonish not only the Australian colonies, but the whole world".