The last confirmed sighting of the suspect, Michael Brown, was on Aug. 1, officials reported on Tuesday, July 5.

The manhunt for an Army veteran suspected of killing four people at a bar he frequented has expanded in the rugged Montana terrain, even as some fear the fugitive may return to the area, authorities said.

Authorities are searching for Army veteran Michael Paul Brown, accused of shooting dead Nancy Kelley, Daniel Baillie, David Leach and Tony Palm inside a bar in Anaconda

Stymied by treacherous terrain and untamed wilderness, authorities are struggling to find an Army veteran suspected of killing four people at a Montana bar. But the difficult landscape isn’t the only challenge.

As the search for Michael Paul Brown continued, Montana Gov. Greg Gianforte signed an executive order freeing up more resources for local law enforcement.

Officers are "unrelenting in their pursuit, working around the clock" to find him, Montana Gov. Greg Gianforte stressed at a news conference on Tuesday. "Rest assured, our brave men and women of law enforcement aren’t giving up."