Less than a week after he was acquitted in a double murder trial, Aaron Hernandez’s suicide early Wednesday morning sent shockwaves across New England.

The former Patriots tight end was still serving a life sentence for his 2015 conviction for murdering his friend Odin Lloyd in 2013. The 2015 conviction will reportedly be voided in the wake of Hernandez’s suicide Wednesday.

Here’s what we know about Hernandez’s suicide and the circumstances surrounding the unexpected tragedy.

The suicide

According to a statement from the Massachusetts Department of Correction, Hernandez was found shortly after 3 a.m. in his single cell at Souza-Baranowski Correctional Center, a maximum-security prison in Shirley.

Officials said he hanged himself using a bed sheet that he had tied to his cell window. Hernandez has also attempted to block the entrance to his cell by jamming the door with “various items.”

Officials said they tried to revive Hernandez at the scene before taking him to UMass Memorial-HealthAlliance Hospital in Leominster. He was officially pronounced dead at 4:07 a.m.

Christopher Fallon, a spokesman for the prison, said officials are unaware of any suicide note.

State police are investigating the hanging.

The prison

The Boston Globe reported Wednesday that Hernandez’s death is the first reported successful suicide by an inmate hanging a sheet from a window at the Shirley prison. Inmate advocates say the prison’s windows are designed to make such attempts difficult.

Since the prison opened in 1998, Souza-Baranowski has had a speckled history of violence, including attacks on prison staff and inmates. According to the Globe, Hernandez is the 27th recorded suicide at the prison since 2010.

As the Globe also reported Wednesday, Massachusetts had the fourth-highest rate of prison suicides in the country from 2001 to 2014.

Hernandez’s mental state

Hernandez was not on suicide watch at the time of his death, Fallon said, and would have been transferred to a mental-health unit if officials had any worries.

But according to reports by the Globe, TMZ and Yahoo! Sports, Hernandez had previously been placed on suicide watch at other prisons — both in 2013 following his initial arrest for murdering Lloyd and in 2015 after his conviction.

An anonymous source told the Globe that despite Hernandez’s stoic demeanor in court, he was “insecure and clung to gang members for approval” in prison.

Yahoo! Sports reporter Dan Wetzel, who covered both Hernandez trials, wrote Wednesday that he noticed a change in the former football star’s attitude during his “final days.” According to Wetzel, as the second murder trial progressed, Hernandez — facing a life of relative isolation — increasingly began to talk and joke with others in the courtroom.

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