Then, At 1:55 a.m. this chilling call was placed from Glass' cell phone.
"911 What's the address of the emergency? Whether or not you're a dead man. Hang up. Six hours later, this call was made to 911 from a Geo prison officer.
"We have a beat down. We have a serious head trauma." Lawton police say Glass was taken to the prison infirmary, then to Medical Center where he was pronounced dead.
No charges have been filed, and police have questioned Glass's cellmate. Investigators say there were no visible puncture wounds on his body, so they're currently waiting on a toxicology report to determine what caused his death.
Glass had been in and out of prison numerous times since 2004 mostly on drug related convictions. His current six year sentence was for bringing contraband into a penal institution.
The investigation continues into the cause of his death which was Lawton's third homicide of the year.
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