Donato Anthony Corbo was born in 1971 in Australia. At the time of the incident, he was 39 years old and resided in Hectorville, a suburb east of Adelaide, South Australia. Corbo had a history of mental health issues, which were exacerbated following a relationship breakup in December 2010. He lived with his father, Giuseppe Corbo, who legally owned several firearms. It is believed that Donato accessed one of these firearms, a shotgun, which he used during the 2011 siege. Prior to the incident, there had been tensions between Corbo and his neighbors, possibly related to the poisoning of Corbo's pet dog.

In the early hours of 29 April 2011, around 2:30 a.m., Donato Corbo entered his neighbors' residence on Montacute Road in Hectorville. Armed with a shotgun, he fatally shot 64-year-old Kobus Snyman, his 65-year-old wife Annetjie Snyman, and their 41-year-old son-in-law, Luc Mombers. A female resident managed to escape the house with her 14-year-old son, Marcel, and his 11-year-old friend. As they fled, Corbo shot and seriously wounded Marcel.

South Australia Police officers responded to the emergency call. Upon arrival, Corbo fired at them, seriously injuring one officer in the face and wounding another in the knee. Despite their injuries, the officers managed to retreat to safety. Corbo then returned to his residence, leading to an eight-hour standoff with the Special Tasks and Rescue (STAR) unit. The siege concluded with Corbo's arrest without further casualties.

On 17 May 2012, the Supreme Court of South Australia found Corbo not guilty of three counts of murder, two counts of attempted murder, and one count of aggravated threatening life, all due to mental incompetence. He was sentenced to three consecutive terms of detention in a mental health facility for life. As of August 2021, Corbo's legal representatives have applied for supervised community release, proposing brief periods of escorted leave under strict supervision.