Pima County Sheriff's Department, Search and Rescue posted a warning on its Twitter feed Monday about hiking in the Marshall Gulch area, just south of Summerhaven.
The post said three recent searches had originated in that area, and that hikers were "dropping into Sabino Creek," which "leads to difficult terrain and no actual trail to follow."
PCSD advised hikers to make sure that they are on the correct trail when leaving the gulch.
The Forest Service's Marshall Gulch Picnic Area website said both the Marshall Gulch Trail and Aspen Trail, which start at the site, "provide access from the picnic area to the Santa Catalina Natural Area, and connect to a broader network of trails on the southwestern slopes and canyons of the mountain range."