Important Information About Scary Assault At Hyalite Reservoir

Authorities in Gallatin County are actively investigating a reported assault at Hyalite Reservoir and are asking the public for assistance. The incident occurred around 10:30 p.m. on Monday, September 1, 2025, near the public restrooms in the day-use area by the dam.

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Deputies, with support from U.S. Forest Service officers, immediately responded, deploying drones and K9 units to search the surrounding area. Despite a thorough search, the suspect was not located.

Officials Warn Public After Attempted Assault at Hyalite Dam

According to the Gallatin County Sheriff's Office, a man allegedly approached a woman from behind under cover of darkness. The victim was able to fend off the attacker by using pepper spray, prompting the suspect to flee.

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The suspect is described as a Caucasian man, middle-aged, with a slim build and curly or wavy auburn hair.

Investigators have since received a tip about a man resembling the suspect who was spotted in the area a day prior to the incident. Witnesses reported he was driving an older Dodge pickup, blue or green in color, heavily faded, and with a rusted bed.

The man was accompanied by a dog, believed to be a pointer breed, wearing a red collar. Authorities are now working to determine whether this person is connected to the case.

The Gallatin County Sheriff’s Office urges anyone visiting Hyalite Reservoir to remain alert, travel with companions whenever possible, and immediately report any suspicious behavior matching these descriptions.

Anyone with information about the suspect, the truck, or the incident itself is asked to contact the Sheriff’s Office Detective Division at 406-582-2121 (voicemail available), call dispatch at 406-582-2100 for urgent tips, or email Detective Sandy Schroeder at sandy.schroeder@gallatin.mt.gov.