A fifth inmate has died violently in a Mississippi prison, as clashes between prisoners continue.

Sunflower County Coroner Heather Burton tells local news outlets that 36-year-old Dennoris Howell was stabbed to death before dawn Friday at the Mississippi State Penitentiary at Parchman. Howell is the fifth inmate to be killed by another inmate since Sunday, and the third at Parchman.

Another inmate was stabbed in the 3 a.m. Friday incident and taken to a Memphis, Tennessee, hospital.

Some local officials have described the violence as gang-related, but state officials haven’t said what’s driving the violence.

All state prisons statewide are locked down, confining inmates to cells and blocking visitors.