A former major at the Louisiana State Penitentiary at Angola admitted Thursday in Baton Rouge federal court that he falsified records to obstruct a federal investigation of an inmate beating by other officers.

Kevin L. Groom Sr., 45, a former major at Angola, also pleaded guilty to a charge that he made a false statement to FBI agents investigating the beating.

“This investigation is ongoing,” U.S. Attorney Donald J. Cazayoux Jr. said after Groom entered his guilty pleas before U.S. District Judge James J. Brady. “It is open.”

No other names are contained in Groom’s charges, which were sealed by court order on Nov. 26. Brady ordered the charges unsealed on Wednesday.

According to the unsealed court record, Groom witnessed the beating in January 2010 of an inmate identified only as “R.M.”

After the Justice Department and FBI initiated the federal investigation, Groom falsely reported in an official document, “At no time did I see anyone hit (R.M) with their fist (or baton) or strike (R.M.) in the truck,” Groom’s charges show.

On Sept. 28, 2011, Groom falsely told FBI agents that on Jan. 24, 2010, “correctional officers did not assault R.M., a handcuffed inmate, while they were transporting R.M. to the medical unit,” Groom’s charges show.

The charges to which Groom pleaded guilty carry combined penalties totaling as much as 25 years in prison and fines that could total $500,000, Cazayoux said in a statement.

“R.M.” was reported to have attempted an escape from Angola, but surrendered to prison officials and was standing near a truck with his hands cuffed behind his back, Cazayoux added.

When Groom arrived at the scene, he saw two prison officers, “C.B.” and “M.S.” with “R.M” at the back of the pickup, Cazayoux said. Three high-ranking prison officials also were present, and one of them “grabbed R.M.’s head and slammed it against the truck,” Cazayoux reported.

“M.S.” then hit “R.M.” with a baton, and “C.B.” struck the inmate as he lay face down in the bed of the truck, Cazayoux added.

The high-ranking officials, who were not identified in court records, ordered Groom to accompany the two officers and “R.M.” on the pickup truck ride to the prison’s medical unit, Cazayoux said. “C.B.” and “M.S.” are alleged to have continued beating the inmate during the drive to that unit.

Cazayoux said Groom’s investigation was conducted by FBI Special Agent Taneka Harris, Justice Department trial attorney AeaJean Cha and Assistant U.S. Attorney Robert W. Piedrahita.

Groom’s attorney is Carl J. Jackson.