ABILENE,TX (KRBC)- The family of slain Correctional Officer Marianne Johnson tells KRBC News they’re questioning the information released about her murder.

Our Shannon Valladolid spoke with the victim’s sister, who says they deserve to know the truth.

It’s been over a month since Johnson was murdered by an inmate at the Robertson Prison Unit and still the family has no idea how it happened.

“I just don’t believe they’re coming out with all the truthful information,” says Leni Atkinson, Marianne’s sister.

Atkinson says these past few weeks she’s received more information from employees at the prison than the Texas Department of Criminal Justice.

“If my sister did indeed die in such a brutal manner, I think we all deserve to know, it’s horrible but we do want justice for Marianne,” says Atkinson. “She was indeed raped and strangled.”

TDCJ has not confirmed these allegations but they say the department is currently conducting a serious incident review and at least 4 employees are involved in that investigation.

Atkinson also believes the reports that Johnson was pronounced at the hospital are false.

“I believe she was dead at the prison and they all know she was dead at the prison and keep saying she died at the hospital,” says Atkinson.

The family of Johnson say they won’t stop until they know the truth.

TDCJ  would not directly confirm any of this information.

Earlier this month, the agency took disciplinary action with 4 employees .

The investigation is still ongoing.