TENNESSEE COLONY, Texas (KETK) – An officer at an East Texas prison was arrested after a random vehicle search produced a suspicious substance.

According to the Texas Department of Criminal Justice, staff at the H. H. Coffield Unit found three vacuum-sealed bags of a “green leafy substance” while doing random searches of employee vehicles entering the unit on June 30.

Officer Diana Ngyangau was arrested by investigators from the Office of the Inspector General for introduction of K2 and was drug tested.

TDCJ officials said she worked at that unit for 29 months prior to the incident.

The Coffield Unit has 518 employees and can house around 4,000 inmates. It is located five miles southwest of Tennessee Colony on FM 2054.