MILFORD, Mass. --Former NFL star Aaron Hernandez apparently hanged himself Wednesday in the prison cell where he was serving a life sentence for murder, taking his life on the same day his ex-teammates on the New England Patriots were set to visit the White House to mark their Super Bowl victory.
Guards found Hernandez just after 3 a.m., Correction Department spokesman Christopher Fallon said. The onetime tight end was taken to a hospital and pronounced dead about an hour later. An autopsy was scheduled for Wednesday in Boston.
Hernandez had been housed in a single cell in a general population unit at the maximum-security state prison in Shirley. He apparently tried to jam the cell door to prevent guards from opening it and hanged himself with a bedsheet tied to a window, Fallon said.
Fallon said he was not aware of any suicide note. Hernandez was not on suicide watch, authorities said. Fallon said officials had no reason to believe Hernandez might take his life, and if they had had any such worries, he would have been transferred to a mental health unit.
His death came just days after the 27-year-old athlete was acquitted in a second murder case.
Those who knew Hernandez said Wednesday they doubted he would commit suicide.
"Absolutely no chance he took his own life. Chico was not a saint, but my family and I loved him and he would never take his own life," wrote Brian Murphy, one of Hernandez's agents.
"There were no conversations or correspondence from Aaron to his family or legal team that would have indicated anything like this was possible," said Defense Attorney Jose Baez, who argued for Hernandez's acquittal.
Michele Steele joined ESPN's Boston bureau four years ago, on the day Hernandez was taken into custody.
"I was absolutely shocked. From everyone I had talked to who was close to him, they said he remained positive when he was in prison," Steele said. "He was friends with some of his cell mates when he was in prison. He was a relatively popular guy, obviously. He was a world-class athlete whose name was very, very well-known in Massachusetts. His agent actually texted me and said he would never kill himself."
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Authorities said Hernandez had a brief history of fights while in custody. In May 2015, Hernandez agreed to be a lookout for an inmate who fought another inmate at the prison where he died. In Feb. 2014, Hernandez and another inmate exchanged words at Bristol County House of Correction before he punched the inmate, knocking him to the ground.
Hernandez helped the University of Florida win the 2008 NCAA championship, but he dropped to the fourth round of the NFL draft because of his behavior of college, where he failed a drug test, he was accused of punching a bar employee, and his name came up in an investigation into a shooting.
He was a productive tight end for the Patriots for three seasons, catching 79 passes for 910 yards and seven touchdowns in his second year to help the team reach the Super Bowl. In 2012, he signed a five-year, $40 million contract extension.
Two years later, Hernandez was unable to even watch his former team play on television while he was in prison awaiting trial in one shooting and already a suspect in another.
The team released him in June 2013, shortly after he was arrested in the killing of Odin Lloyd, a semi-professional football player who was dating the sister of Hernandez's fiancee. He was convicted and sentenced to life without the possibility of parole.
Last Friday, Hernandez was acquitted in the deadly 2012 drive-by shootings of two men in Boston. Prosecutors said he gunned them down after one of them accidentally spilled a drink on him in a Boston nightclub.
As the jury was deliberating last week, cameras spied Hernandez blowing kisses to the young daughter he fathered with fiancée Shayanna Jenkins.
His death was "a shocking and sad end to a very tragic series of events that has negatively impacted a number of families," said Bristol County District Attorney Thomas Quinn, who prosecuted Hernandez in the Lloyd case.
Prosecutors suggested Lloyd may have been killed to keep him quiet about the 2012 Boston killings.
Massachusetts State Police, the Worcester County District Attorney's Office and the Correction Department are investigating the death.
Team spokesman Stacey James said the Patriots were aware of the reports of Hernandez's death but didn't anticipate the club commenting Wednesday.
With regard to the team's White House visit, Quarterback Tom Brady said he would not attend the ceremony. He released a statement Wednesday that explains why:
"I am so happy and excited that our team is being honored at the White House today. Our team has accomplished something very special that we are all proud of and will be for years to come. Thank you to the President for hosting this honorary celebration and for supporting our team for as long as I can remember. In light of some recent developments, I am unable to attend today's ceremony, as I am attending to some personal family matters. Hopefully, if we accomplish the goal of winning a championship in the future years, we will back on the South Lawn again soon. Have a great day!"
WLS-TV contributed to this report.