State investigators have found another case of abuse at Austin’s State Supported Living Center. It’s a story the Nightbeat first reported last week.

Monday the victim’s mom told KVUE it appears the abuse went unreported for 12 hours.

Stephanie Powell said her son Corey Baker may be 17, but he has the mind of a two-year-old. Still he can not forget what happened two months ago at the Austin State Supported Living Center.

"Someone went in there and beat him,” said Powell. “I wasn't there for him. I'm his mom. I'm supposed to protect him. They're supposed to protect him and they didn't."

She got the call a day later at her Forney home near Dallas and rushed to see him.

"There were just bruises here and all down his back you could see the thumb print, fingerprints on his arms," he said.

Cecilia Fedorov with the Department of Aging and Disability Services said the state investigated.

"They did confirm the allegation which led our agency DADS to fire the employee that was involved," said Fedorov.

A federal investigation found dozens of cases of abuse and neglect at 13 state institutions.

DADS has been focused on issues like this since 2005 when a federal investigation found dozens of cases of abuse and neglect at 13 state institutions.

The most recent and most notable case came to light in 2009. Cell phone video from Corpus Christi showed state employees forcing residents to fight.

Since then the state has made changes. It has hired more workers to oversee residents and now requires unannounced spot checks.

"We've also had an independent ombudsman, as well as appointed three independent monitors that were jointly selected by the state of Texas and the Department of Justice," said Fedorov.

The state also began installing video surveillance cameras inside all of its living centers, but it's unclear whether there's video of Corey’s incident.

Since September of last year there have been 275 allegations of abuse at the Austin State Supported Living Center, 28 cases of abuse were confirmed.

Corey's mom says one case is one too many.

“That's my son,” said Powell. “That's my baby."

Now home, Corey will only sleep with the door open and the hallway light on.

"And my bedroom door has to stay open," she said.

No criminal charges have been filed against the state worker. He had only worked at the center for a month and did not have a criminal background.