PHOENIX — The Scottsdale Police Department is investigating the death of a 57-year-old Rhode Island woman who was found on an Arizona hiking trail Sunday night, authorities said.

The woman, identified as Donna Miller, was hiking the Brown’s Ranch hiking trail system around noon, located near Alma School Road and Rio Verde Drive, with her husband.

Miller’s husband called police around 3:15 p.m. when he couldn’t find her at their meeting spot after a planned separation, authorities said in a press release.

Rescue team members found Miller’s body around 9 p.m. following a large-scale search involving search dogs, as well as two fire departments.

Authorities said in the release that the cause of death “appears to be due to heat-related illness and environmental exposure.”