On the night of July 30, 2016, a house party in Mukilteo, Washington, attended by about fifteen to twenty young people ended in a rapid, deadly attack. Nineteen-year-old Jordan Michael Ebner, a Caucasian local, was one of three people killed when a former classmate, 19-year-old Allen Christopher Ivanov, opened fire shortly after midnight. Victims Jake Long and Anna Bui, both 19, were also killed; a fourth person, Will Kramer, was seriously injured and survived. The entire shooting lasted roughly 35 seconds.

Ivanov arrived unarmed, then retrieved an AR-15-style rifle from his vehicle and concealed himself near the house. After killing Long, he shot others outside, including Ebner, then entered the home and shot his ex-girlfriend Anna Bui multiple times. He ran out of ammunition, fled, and was arrested about ninety minutes later near Chehalis after police pinged his cellphone. Officers recovered an AR-15-type rifle and two magazines in his car.

Ivanov told investigators he was motivated by jealousy over his breakup with Bui and had made troubling social media posts in the days before the attack; he had purchased the rifle a week earlier. He was charged with aggravated first-degree murder, attempted murder and first-degree assault, initially pleaded not guilty, then pleaded guilty in December 2016 and was sentenced on January 12, 2017, to life without parole.