The Gallatin County Sheriff’s Office, with assistance from the U.S. Forest Service, is investigating an assault that occurred at approximately 10:30 p.m. on Monday, Sept. 1, 2025, near the restrooms in the day-use area by the dam at Hyalite Reservoir.

According to the report, a male suspect approached a female from behind under the cover of darkness. The suspect fled the scene after the victim deployed pepper spray in self-defense.

The suspect is described as a middle-aged Caucasian male with curly or wavy auburn-colored hair and a slender build.

Deputies responded to the area and deployed drones and K9 units in an effort to locate the suspect. Despite extensive search efforts, the suspect was not located.

A tip has since been received regarding a male matching the suspect’s description who was seen in the area the previous day. The individual was reportedly driving a late-model Dodge pickup with faded blue or green paint and a rusted-out box. He was accompanied by a dog, possibly a pointer, wearing a red collar. Investigators are working to determine whether this individual may be connected to the incident.

The Gallatin County Sheriff’s Office urges community members to remain vigilant while recreating in the area and to report anything matching the descriptions provided. Travel in groups when possible and remain aware of your surroundings.

Anyone with information about the incident, the vehicle, or the individual described is urged to contact the Gallatin County Sheriff’s Office Detective Division at 406-582-2121 and leave a message.

If the information is more urgent, please call dispatch at 406-582-2100. Email tips can also be sent to Detective Sandy Schroeder at sandy.schroeder@gallatin.mt.gov.