The Lewis & Clark County Sheriff's Office is searching for an adult female horseback rider in the McMaster Hills Recreation Area several miles northeast of Helena.
Search & Rescue units from Lewis & Clark County and Jefferson County are on the ground.
Drones from several law enforcement agencies are searching by air.
A helicopter from Great Falls has also been called in to assist.
Officials will be active in the recreation area throughout the majority of the day.
If you have information or would like to offer assistance, please call 406-219-7380.
No other details have been released at this point, including the name of the missing woman.
We will update you if we get more information.
