Authorities in Oklahoma are delving into the tragic circumstances surrounding the death of a 30-year-old middle school teacher. The teacher reportedly passed away after being served an industrial-strength chemical cleaner instead of a margarita at a Mexican restaurant.

The Elgin Police Department has announced they are in “daily contact” with the Oklahoma State Bureau of Investigation (OSBI) as they work on the case involving Holly Hill, who died last week. This information was shared in a recent news release.

“The OSBI will spearhead this investigation, supported by the Elgin Police Department,” stated the police in their announcement. “We have informed Holly’s family and urge the community to extend patience and respect during this difficult time.”

Hill’s untimely death follows a series of health complications that allegedly began when she and her husband dined at Hacienda Las Margaritas Bar & Grill on Valentine’s Day in 2023. This restaurant is located approximately 70 miles southwest of Oklahoma City.

Speaking to Tulsa’s CBS affiliate KOTV, Hill’s mother, Kelly Hunter, described the troubling event. She recounted, “Her mouth felt like it was on fire, and she knew something was terribly wrong. She rushed to the bathroom, began vomiting, and tried to rinse her mouth out with water.”

“Her mouth was on fire, and she knew something wasn’t right,” Hunter told the station. “She immediately jumped up and ran to the bathroom, started throwing up, started rinsing her mouth out with water.”

The report states that the restaurant served Hill industrial-strength degreaser in her margarita. Following the incident, she was reportedly forced to make several trips to the emergency room for medical treatment due to severe chemical burns suffered throughout her esophagus.

In the years since she allegedly ingested the chemical substance, Hill reportedly underwent dozens of surgical procedures. Her most recent surgery took place on Oct. 17, just days before her death.

“As they were trying to get her ready to transport her, they lost her pulse,” her mother told KOTV.

It was not immediately clear why authorities had only just begun investigating Hill’s death.

Hill filed a civil lawsuit against the restaurant in August 2023. The case was dismissed with prejudice earlier this year after Hill and the establishment reached a confidential settlement, her personal injury attorney told KOTV.

While the restaurant has never directly addressed the situation with Hill, it did appear to allude to the situation in a 2023 Facebook post apologizing to the Elgin community.

“We are very sorry for what happened and we feel deeply since the moment it occurred because during these 10 years we have never had a situation like this, a situation that should not have occurred in the first place,” the post said. “We have never walked away from responsibility and will continue to support [Hill and her family] in any way possible while our insurance company is on the case. We have always tried to give back to the community and will continue to do so.”

Hill had been a teacher at Elgin Middle School since 2019. Elgin Public Schools Superintendent Nate Meraz posted about her death on Friday.

“This morning I received the unimaginable call that Holly had passed away unexpectedly,” Meraz wrote. “Holly was a dedicated teacher, Elgin Alumni, and beloved mother and wife. She was an Owl through and through and we lift her family up in prayer tonight.”