The shooting killed three people and injured seven others at a newly opened In-N-Out Burger in Twin Falls, Idaho. RELATED: In-N-Out Burger shooting leaves multiple dead in IdahoPolice said they are confident Williams was the only shooter. The backstory:The shooting unfolded around 2 p.m. Saturday at the recently opened restaurant in a busy shopping plaza. The In-N-Out restaurant had opened July 24 as part of the California-based chain's expansion into Idaho. Twin Falls, a city of about 56,000 residents, is located roughly 130 miles southeast of Boise and about 75 miles north of the Nevada border.