Police were called to the Pinnacle Multicare Nursing and Rehabilitation Center on Friday night.
They say 83-year-old Lloyd Godfrey was found dead with injuries to his head shortly after 11 p.m.
Clifton Bourne, 87, was taken into custody on a charge of murder.
Police say both men suffer from dementia and got into an argument that escalated to a physical altercation.
It is not clear what the dispute was about.
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