Former New England Patriot Aaron Hernandez has died in a Massachusetts jail.

According to the Massachusetts Department of Corrections, Hernandez was discovered hanged in his cell around 3:05 a.m.

Hernandez was pronounced dead at 4:07 a.m. at UMASS Leominster after efforts to save him failed.

A spokesperson for the Department of Corrections says Hernandez was in a single cell in the general population, and used a bed sheet attached to a window to hang himself. The spokesperson says Hernandez also made attempts to block his door with items inside his cell.

The Massachusetts State Police are investigating.

Hernandez was serving a life sentence for the 2013 murder of Odin Lloyd.