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OKLAHOMA CITY - It was a crime that changed the culture of Oklahoma forever.
On July 16, 1978, Roger Dale Stafford went into the Sirloin Stockade in Oklahoma City and attempted to rob the restaurant.
Armed with a handgun, Stafford and his wife and brother went into the restaurant and ordered four of the teenage employees into the freezer.
Officials say Stafford shot 17-year-old David Lindsey, 16-year-old David Salsman, 17-year-old Anthony Tew and 15-year-old Terri Horst execution style.
Stafford also killed 43-year-old Louis Zacarias, the store manager, and 56-year-old Isaac Freeman.
It was a brutal crime that shocked the Sooner State.
"It was almost like a rite of passage for Oklahoma City. We'd never had any; we'd had murders occasionally, but nothing like this," said then-District Attorney Andy Coats.
It was Oklahoma's first mass murder, and it terrified residents.
The panic became worse when authorities were able to link the gun used in the Sirloin Stockade murders to the murders of a North Dakota family in Purcell.
The bodies of 38-year-old Sgt. Melvin Lorenz, 31-year-old Staff Sgt. Linda Lorenz and 12-year-old Richard Lorenz were found along the highway.
After being convicted of the crimes, Stafford was executed in 1995.