Mississippi prisons erupted in violence last week: at least five prisoners were stabbed or beaten to death by other inmates. The Marshall Project has been reporting on prison conditions there for months.

Here are five factors that help explain the mayhem that followed.

  1. Mississippi prisons don’t have nearly enough guards Short staffing is probably the biggest problem facing prisons around the country, and it’s especially acute in Mississippi.
  2. Prisoners in Mississippi are being kept in conditions similar to solitary confinement. With constant short staffing, prison officials often respond with “lockdowns.” Prisoners are kept inside their cells almost 24 hours a day. Lockdowns can go on for months at a time, ratcheting up tensions among prisoners.
  3. Mississippi’s prisons have long been awash in weapons and violence Violence in Mississippi’s prisons has been common for years, according to data acquired by The Marshall Project.
  4. Some staff members have loyalties to particular gangs Gang activity isn’t limited to some of the people incarcerated in Mississippi, according to interviews with more than two dozen former and current state corrections officers.
  5. Cell phones have broken down prison walls Cell phones are extremely common contraband in Mississippi prisons, allowing incarcerated people to communicate with each other within a prison and between prisons, which some sources say is how the violence spread between different prisons last week.

Read the full article about five factors behind the deadly violence at the prison by Joseph Neff and Aylsia Santo at The Marshall Project.