Federal authorities in Mississippi said Tuesday that they are aware of problems in the state’s understaffed prison system, recently shaken by deadly violence.

The special agent in charge of the FBI’s Jackson division and the state’s two U.S. attorneys asked people to provide information if they know of civil rights violations or criminal activity.

“Allegations of the violation and deprivation of civil rights, as well as criminal activity, continue to be taken very seriously by our offices,” said the joint statement by the FBI’s Michelle A. Sutphin and U.S. Attorneys William C. Lamar of the state’s northern district and Mike Hurst of the southern district.

They said people could report potential federal criminal violations to the FBI or potential civil rights violations to the civil rights division of the U.S. Justice Department. They did not say how extensive a federal investigation might be.

Five inmates were killed and an undisclosed number of others were injured in an outburst of violence between Dec. 29 and Jan. 3.

Because of damage caused during the unrest, hundreds of prisoners were moved from one unit at the Mississippi State Penitentiary at Parchman to another unit there that closed years ago because of decrepit conditions.

The state then entered an emergency contract to move 375 of those inmates to a private prison nearby.