In Honolulu, Hawaii, a man fatally stabbed his wife and two children before taking his own life, according to police. In California’s San Luis Obispo County, a family of five was found dead in a burned house in what appeared to be a murder-suicide. In central California, a shooting at an outdoor party killed four people, including one child, and wounded seven others. The attackers were described as wearing dark masks and fleeing the scene in a silver sedan. Authorities believe the motive for the attack may have been gang-related.