Update 3:50 p.m.
The Rosebud County Sheriff's Office reported a "large law enforcement presence" Wednesday afternoon at the St. Labre campus related to the shooting in Lame Deer Tuesday night.
The suspect was described at 5 feet 10 inches tall, 180 to 190 pounds with long brown hair and tattoos on one arm. He is about 31 years old and wearing a brown, long-sleeved shirt, a blue ball cap and gray pants.
The sheriff's office asked residents to avoid the St. Labre campus area and for all Ashland residents to report any unusual or suspicious people, according to a Facebook post.
Anyone with information can call the FBI Salt Lake City Field Office at (801) 579-1400.
LAME DEER - Authorities are warning residents in Lame Deer on the Northern Cheyenne Reservation to be aware of their surroundings following a fatal shooting Tuesday night.
A bulletin from the Northern Cheyenne Tribal Council states "the active shooter is still at large."
Sandra Barker, an FBI spokesperson, confirmed her agency, the BIA and Northern Cheyenne Investigative Services are investigating the fatal shooting of a man in Lame Deer.
Authorities clarified that the shooter is no longer engaged in firing a weapon.
A dispatcher at the Northern Cheyenne Police Department said the incident is an active investigation and no further information could be released. He referred the caller to the FBI for additional details.
Anyone with information is asked to call the FBI Salt Lake City Field Office at (801) 579-1400.
This is a developing story. Check back for updates.