Michael Grief, 30, was being held at the Suffolk County jail in Riverhead, where a guard found him hanging in his cell Friday, according to Newsday. Grief, who was discovered around 4 a.m., was transferred to Peconic Bay Medical Center and then Southside Hospital in Bay Shore. He was pronounced dead at 11:12 p.m. Friday evening. Grief was not on suicide watch when he took his own life.