Quinley Lamb and Brian Shackleford.Photo: Facebook (2)

A 61-year-old Oklahoma man was arrested Saturday on three counts of first-degree murder after authorities claim he called them from a casino slot machine and admitted to killing the three people found last week on his land.
Robert Lewis is charged with the brutal murders of Deanna Tippey, 36, Quinley Lamb, 43, and Brian Shackleford, 51, PEOPLE confirms through online records.
All three bodies were discovered in shallow graves on his Eldon property, Cherokee County Sheriff Jason Channault said during a press conference held Monday.
Tippey, who was Lewis' girlfriend, was strangled to death, according to investigators; Lamb, who had been reported missing out of Arkansas, was beaten to death; and Shackleford died from being stabbed with an unspecified sharp object.
Robert Lewis.Cherokee County Sheriff

“Lewis said he killed Lamb and Shackleford on his birthday, which would be January 16th,” Channault told reporters. “Tippey was killed later.”
Channault said that deputies arrested Lewis at the Cherokee Casino in Tahlequah on Saturday. The accused had called police from the casino floor, where he was playing the slots, and allegedly said he wanted to turn himself in.
“It’s sad anytime we have to respond to something like this, but with the way the bodies were disposed of it just makes it much more sad,” Chennault said, noting a motive for the killings is not yet known.
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Cherokee County District Attorney Jack Thorpe told reporters Monday he may pursue the death penalty against Lewis.
Chennault said investigators plan to return to Lewis' property to search for additional graves.
source: people.com