A district attorney in Tennessee dismissed more than 30 cases involving five former police officers who were charged with second-degree murder in the death of Tyre Nichols, according to a statement obtained by CNN affiliate WHBQ on Wednesday

Shelby County District Attorney Steven Mulroy said his office reviewed approximately 100 cases involving the officers.

In addition to the 30 dismissals, charges were reduced in about a dozen other cases, the district attorney's statement said.

"As in any such case, the primary consideration is concern about the credibility as witnesses of discharged officers," the statement said.

Nichols died a few days after being pulled over and beaten by the former Memphis Police officers on January 7.

Body camera videos and surveillance footage from Nichols' arrest were released on January 27, publicly revealing the severity of the beating, and sparked widespread condemnation from residents and police officials and, the county prosecutor said at the time, contradicting what officers said happened in the initial police report.

The district attorney charged the five Memphis Police officers with second-degree murder in the fatal beating of Nichols. All five were terminated by the Memphis Police Department.

The district attorney's statement noted the former officers are expected to file various pretrial motions and no trial date has yet been set.

The city of Memphis, its police department and the fired officers also face a lawsuit filed by Nichols' family.

In February, Mulroy said the attorney general's office would be reviewing all prior cases involving the five officers.

CNN has reached out to the Shelby County District Attorney's Office but has not received a response.