Manhunt intensifies for Montana bar shooting suspect, 38 agencies part of the 'unrelenting' search

Michael Paul Brown, 45, fled the scene after the Friday morning shooting.

A manhunt is intensifying for the former U.S. Army soldier who's been at large for days after allegedly gunning down four people at a Montana bar.

Michael Paul Brown, 45, is suspected of opening fire on Friday morning at The Owl Bar in Anaconda, a city of about 9,000 people in southwestern Montana, authorities said.

There has not been a confirmed sighting of Brown since Friday, authorities said.

Thirty-eight local, state and federal agencies are involved in the search, Anaconda Deer Lodge County Attorney Morgan Smith said.

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."

The governor said he signed an executive order to use financial resources from the state emergency respond fund to help support law enforcement, including overtime.

"This action today will ensure additional financial resources are available as we continue to track down this criminal," Gianforte said.

The governor opened Tuesday's news conference with a moment of silence for the four victims, identified as bartender Nancy Loretta Kelly, 64, and patrons Daniel Edwin Bailey, 59; David Allen Leach, 70; and Tony Wayne Palm, 74.

Brown lived next door to the bar and investigators believe he was familiar with most of the victims, authorities said.

To the families, Smith said at the news conference, "Our thoughts and prayers remain with you."

Brown is an Army veteran who served in the Iraq War and the Montana National Guard, according to Montana Attorney General Austin Knudsen.

Brown is known to law enforcement, Knudsen said, and is believed to be armed and extremely dangerous.

A $10,000 reward has been offered by the U.S. Marshals Service for any information leading to Brown’s capture, Knudsen said. He asked anyone with information to call 1-877-WANTED2.

His brother, William Brown, is currently serving a life sentence in prison for murder in the same community, the Montana Department of Corrections confirmed to ABC News. William Brown was convicted of murder in 2000 and, a year later, was convicted of escaping jail.

He was sentenced in 2002.