David Malcolm Gray was a reclusive man who lived alone in the quiet seaside town of Aramoana, New Zealand. Born on November 20, 1956, Gray had a troubled personality and was known in his neighborhood for being antisocial and paranoid. His mental health appeared to deteriorate over time, and he reportedly had increasing conflicts with his neighbors. Gray was a firearms enthusiast and owned several guns legally. In the years leading up to the massacre, he became more withdrawn and aggressive, often ranting about conspiracies and threats he believed were targeting him.

On November 13, 1990, David Gray launched one of the deadliest mass shootings in New Zealand history. It began with a verbal dispute with his neighbor, after which Gray retrieved a semi-automatic rifle and fatally shot the man. He then went on a shooting rampage throughout Aramoana, a quiet seaside town, killing a total of 13 people, including children and police Sergeant Stewart Guthrie, who was the first officer to respond to the chaos.

Gray used multiple firearms and moved from house to house, setting some properties on fire and targeting anyone he encountered. The massacre lasted overnight, with terrified residents hiding or fleeing as Gray terrorized the neighborhood. The next day, elite units from the Anti-Terrorist Squad (now the Special Tactics Group) conducted a careful house-by-house search. Gray was located on November 14, and during a confrontation, he emerged from a home firing from the hip. Officers returned fire, shooting and injuring him. He died shortly afterward in an ambulance en route to the hospital.