Officers responded to the Mesa Regal RV Resort about 10:30 a.m. Friday and found a woman in her late 40s with multiple wounds.
The woman was taken to a hospital, where she was listed in critical but stable condition. Her name wasn't immediately released.
Police say they found a vacant mobile home on the west side of the park with signs of forced entry.
A perimeter was established and negotiation attempts were initiated.
After a few hours without a response, officers entered the mobile home and found a man in his early 20s dead from an apparent self-inflicted gunshot wound.
Police haven't released his identity or a possible motive in the case.
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