Crandon shooting

The Crandon shooting was a mass murder that occurred about 2:45 a.m. CDT on October 7, 2007, at a post-homecoming party inside a duplex in Crandon, Wisconsin, United States. The perpetrator, 20-year-old Tyler James Peterson (March 6, 1987 – October 7, 2007), who was a full-time deputy in the Forest County Sheriff's Department and a part-time officer with the Crandon Police Department, shot and killed six people and critically injured a seventh before committing suicide. One of the victims, 18-year-old Jordanne Michele Murray, was Peterson's former girlfriend, and it was believed that a dispute within the apartment motivated the shooting.

The incident was retroactively identified as the first time an AR-15 style rifle was used in a mass shooting in the U.S., according to ''Mother Jones''s mass shooting database; AR-15s have been used in mass shootings at increasing rates since the Crandon shooting. Provided by Wikipedia