The Georgia Bureau of Investigation says its aware of a report detailing an alleged confession by Ryan Duke that's circulating the internet.

Duke is the man charged with murdering Irwin County teacher and beauty queen, Tara Grinstead, in 2005.

GBI Special Agent JT Ricketson says he cannot confirm if the documents came from the GBI case file, but he did say he's contacted both District Attorneys involved in the case about the alleged leak.

MORE: Tara Grinstead | Top 5 things to know about the murder case, arrests (March 2017)

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The 11-page document first appeared on the Up and Vanished discussion page last week -- a website dedicated to a podcast created by Atlanta filmmaker Payne Lindsey about the disappearance of Tara Grinstead.

The post has since been deleted, but the documents appear to come from the Grinstead case file, which the GBI has called the largest in their history.

RELATED: Documents say accused Grinstead killer may have confessed in 2005

They appear to document Duke's February 2017 confession to GBI agents. He's quoted as saying "I was involved with it, man."

According to the files, Duke told agents that the night he broke into Grinstead's Ocilla home, he was drunk and high, and went to steal money to buy drugs.

When she "surprised" him, it says he "struck her with his fist" out of fear.

Duke allegedly said that he ran out and then called the home from a pay phone to see if Grinstead would answer. When she didn't, the file says Duke said he knew she must be dead.

"The fact that Duke knew about the telephone call was knowledge only known by the GBI and guilty persons," an agent allegedly wrote.

The documents say Duke brought latex gloves and a quilt back to Grinstead's home that night.

He allegedly put her body into a pickup, owned by his friend Bo Dukes, and dumped the body at a pecan orchard.

Days later, the file says Duke and Dukes moved her body deeper into the woods and burned it.

Investigators still won't say if they've recovered Tara Grinstead's remains.

Within the alleged confession, Duke tells agents, "I know I'm going to prison, I waive my rights to a lawyer and I'm willing to cooperate fully."

In August, Duke's public defender filed a motion to suppress any statements he made to law enforcement while in custody last year. Duke's lawyer argues that he made those statements without a lawyer present.

At this point it's unclear who posted these documents online.

Ricketson says the GBI has released only two copies of the case file to two district attorneys -- Paul Bowden and Brad Rigby -- involved in the case.

Duke's recently hired defense attorney Ashleigh Merchant told 13WMAZ that she does not know who posted the documents either and would not comment further.

WMAZ also asked both district attorneys involved on the case for comment.

Bowden was out of the office Monday, and Rigby said he couldn't confirm or deny the validity of the confession.