ANACONDA, Mont. (AP) — Montana Gov. Greg Gianforte on Tuesday signed an executive order freeing up more resources for local law enforcement as they searched a mountainous area for a former U.S. soldier suspected of killing four people at a bar last week.

The search for Michael Paul Brown stretched into its fifth day with more than three dozen law enforcement agencies helping with an effort that Montana's top officials described during a news conference as the highest priority in the state.

A team with the Montana National Guard has flown nearly 20 hours since last Friday, looking for any clues for Brown's whereabouts as an undisclosed number of officers searched on foot.

"Rest assured, our brave men and women of law enforcement aren’t giving up, and I ask that you not give up on them either,” Gianforte said.

Authorities say Michael Paul Brown, 45, fatally shot four people last Friday at The Owl Bar in the small town of Anaconda with a rifle that police believe was his personal weapon. He fled in a white pickup that he later ditched and stole another white vehicle stocked with clothes, shoes and other supplies.

A female bartender and three male patrons were killed. The shooting rattled the tight-knit town of about 9,000 people, and many residents remain on high alert with the suspect still at large.

Montana Attorney General Austin Knudsen reiterated Tuesday that authorities are operating under the assumption that Brown is armed and extremely dangerous.

Without providing more details, Knudsen said there's evidence that authorities are searching in the right area. He added that it does not appear that Brown has broken into any cabins or homes in the area to get food or additional supplies.

Federal authorities were offering a reward of up to $10,000 for any information leading to Brown’s capture.

Family members have said Brown has struggled with mental illness for years, and they had sought help for him.

Brown served in the Army as an armor crewman from 2001 to 2005 and deployed to Iraq from early 2004 until March 2005. He also was in the Montana National Guard from 2006 to March 2009.