Aaron Hernandez Prison Letter to Be Auctioned Off

A letter written in prison by former NFL player Aaron Hernandez is now being auctioned off.

USA Today reports that Hernandez wrote the letter, written in blue ink on yellow legal paper while in prison and was penned just 13 days after his arrest.

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According to the publication, the letter, dated July 8, 2013, will be auctioned off at the Lelands Masters Auction and includes a discretion shared by Hernandez.

"Please keep this private [and] off social media [because] they will make it into a huge thing positive or negative you never know!" the bottom of the first page reads.

The recipient of the letter will not be revealed, but the original envelope from the Bristol County Sheriff's Office will be included.

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As of Thursday, the opening bid was $300.

Earlier this week, attorneys representing Hernandez refiled a lawsuit against the NFL and its former helmet manufacturer. In the documents, the lawyers claim that the 27-year-old former football player "had a horrendous existence" as a result of a severe chronic traumatic encephalopathy (CTE), which is a degenerative brain disease linked to head trauma.

The complaint, which was obtained by PEOPLE, lays out Hernandez's estate's claim that the former New England Patriot sustained multiple hits to the head while wearing Riddell helmets. Hernandez reportedly suffered from Stage 3 CTE from the injuries, which was a rarity in football players at his age.

In April 2017, Hernandez, 27 died by suicide while serving a life without parole for murdering Odin L. Lloyd in North Attleborough in 2013.

The former New England Patriots player was discovered hanging in his cell at the Souza Baranowski Correctional Center in Shirley, Massachusetts.