Aaron Hernandez, the 27-year-old former NFL star who killed himself in a Massachusetts prison on Wednesday morning, was not on suicide watch. Christopher Fallon, spokesman for the state’s Department of Corrections, said Hernandez never indicated he might harm himself. “If he had made any kind of statement, he would have not been in that unit,’’ said Fallon. Officials said they also haven’t found any evidence of a suicide note left behind by the former New England Patriots tight end when he used a prison bedsheet to hang himself from a window. Massachusetts State Police are investigating his death.