Updated

State investigators want to know why surveillance tapes from a troubled youth prison — allegedly showing a former guard entering a supply closet with a teenage girl — were never shown to the grand jury that cleared the guard of abusing the girl and two others.

The tapes were discovered at Texas Youth Commission headquarters in Austin on Friday, nine days after the grand jury decided not to indict the former guard at the Ron Jackson facility in Brownwood.

After learning that no indictment had been returned, Richard Steptoe, an investigator with the Texas Department of Criminal Justice Inspector General's office, asked TYC officials to show him the collected evidence. He had the three or four tapes within minutes. The inspector's office has been called to assist the investigation of sexual and physical abuse cases at TYC.

"We don't know if they were misplaced or concealed," Steptoe's boss, John Moriarty, TDCJ's inspector general, told the San Antonio Express-News. "We're looking into it. I would certainly say (the tapes) are material to the case."

The Brown County district attorney's office didn't immediately return phone calls to The Associated Press on Tuesday.

In 2005, the TYC said it confirmed the guard had sexually abused at least three girls at the Brownwood facility. The official report stated that the footage supported details given by each of the three girls.

The girls told investigators the guard used the supply closet to have sex with them. The tapes allegedly show the seven-year-veteran, over a number of days in 2004, entering and exiting the supply closet with at least one of the girls.

"Several times that day (the alleged victim) went into the closet followed by (the guard) a few minutes later," the report stated.

The guard was allowed to resign. The case was forwarded to the local district attorney after the more publicized sex abuse scandal at the West Texas TYC facility broke in February.