PORT ALLEN- The family of 54-year old Robert Gash is demanding an explanation after their loved one managed to go unsupervised for hours at Legacy Nursing Home and then died outside the facility.

The WBRZ Investigative Unit learned a criminal investigation is underway at the Port Allen Police Department.

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A fact of death letter determined that Gash died of a heart attack and hypothermia. Sources told WBRZ Gash got out of the nursing home around 2 a.m. He wouldn't be found for hours and was pronounced dead at 6:51 a.m. on Nov. 24.

"Y'all just sitting in a nursing home not paying attention to these people," said Yolanda Gash, Robert's sister. "That nursing home should not be open any longer. The ones that do right, I feel sorry for them. But y'all know what everyone else is doing. Y'all didn't pay attention to our loved one."

Gash said her brother was a mental health patient and was living at the facility. She received a call on Thanksgiving Day from a worker who called her from a cell phone.

"I feel bad because if I knew my brother wanted to go home because he was being neglected, I would have gotten my brother out of that place," Gash said. "I was the last one he spoke to. We were going there to get him Thanksgiving morning, and they told me he was dead."

Gash said when she began asking questions about her brother, she was originally told that he died of high blood pressure. But, an autopsy revealed he died from hypothermia and a heart attack.

"I don't know what my brother did to deserve that," Gash said. "If y'all couldn't take care of him, y'all shouldn't have taken that responsibility. The way you treated him like a dog, and I don't think it's fair to be still working inside that nursing home. It's hard because we have no money to bury my brother, and for y'all not to reach out... y'all never picked up the phone from the supervisors, administration office. No one called us, and my brother was left there dead all that time."

The Executive Vice President of Legacy Nursing home said, "It is the policy of Legacy Nursing & Rehabilitation to ensure that family members and responsible parties are always notified when there is any change in the health of a resident. We make multiple attempts to contact responsible parties to keep them well informed and aware. The resident was never missing and we do not have information to support your claim."