The Sweet Grass County Sheriff's Office is asking for help finding a teenager who went missing from Big Timber.
Marshall Dammann, 16, was last seen on the evening of June 29. Authorities believe he may have planned to travel to Great Falls. State officials issued a Missing and Endangered Person Advisory on Wednesday that said he may also have planned to travel to Livingston.
Dammann is five-feet, seven-inches tall with dark blonde hair, blue eyes, and a pale complexion, and weighs 160 pounds. He was last seen wearing a white and gray sweatshirt with blue jeans and white tennis shoes.
Sweet Grass County Sheriff Alan Ronneburg said there wasn't any reason to suspect foul play at the time of Damman's disappearance, but that the amount of time he has been missing is concerning.
"It's been three weeks. Usually when we get kids that kind of run away, we actually find them within 72 hours to a week. They aren't gone this long," he said.
"He'll greet you as a really friendly kid. It's very uncharacteristic of him to do this kind of thing," Ronneburg said.
Police did receive a tip yesterday that Dammann was seen at a gas station in Great Falls, but Ronneburg said they haven't been able to substantiate or confirm it.
Anyone with information on Dammann's whereabouts should call the Sweet Grass County Sheriff's Office at 406-932-5143.