(KRON) — Three residents of an assisted living facility were mistakenly served dishwashing liquid as drinking juice and one has since passed away, Nexstar’s KRON has learned.

Around 8:30 a.m. Saturday, three ambulances were called to the Atria Park Senior Living facility in San Mateo, California, to treat patients, according to San Mateo Consolidated Fire. Three people were taken to a hospital after “mistakenly being served dishwashing liquid as drinking juice,” Atria Park confirmed in a statement to KRON.

KRON spoke with one family who said their loved one passed away after the incident. Marcia Cutchin said that her family first heard of the incident involving her mother, 93-year-old Gertrude Elizabeth Murison Maxwell, when an Atria staff member called to report that she had ingested a substance and an ambulance was being called.

Atria told her family the substance was an “alkaline cleaning solution that eats protein,” when they were first informed of the incident.

Cutchin explained Maxwell arrived at the hospital with “severe blistering of her mouth and throat and esophagus.” Upon her arrival at the hospital, Maxwell’s family was told there was nothing the medical team could do to treat the blistering.  

According to Cutchin, she and her family were told first responders believed the dementia patients had ingested the substance on their own. It would be impossible for Maxwell to do that, Cutchin said, because her mother couldn’t feed herself.

“Many people, like my mother, you have to hold a cup to her mouth and tip it into her mouth,” Cutchin said.

Maxwell leaves eight children and 20 grandchildren behind.

KRON reached out to Atria Senior Living and received the following statement in response:

“We can confirm three of our residents were recently transported to the hospital after mistakenly being served dishwashing liquid as drinking juice. We have been working with local authorities, who have informed us that one resident passed away. Our sincerest condolences are with the family. When this occurred, our staff immediately contacted authorities, and the residents were transported to the hospital for evaluation and treatment. We are conducting our own internal investigation, and the employees involved have been suspended until this investigation concludes. We will continue working with the police and Department of Social Services to fully review and assess the incident, after which we will take additional actions as needed. The safety and well-being of our residents remain our top priorities at all times. Out of respect for the people involved, we cannot comment further.”

Atria Senior Living

As of Monday night, San Mateo police are continuing to investigate the incident and have not shared any additional information. They say Atria is cooperating with the investigation.