Authorities said the suspect in a shooting at The Owl Bar in Anaconda, Montana, was believed to be armed and dangerous.

A manhunt is intensifying for the gunman who allegedly killed a bartender and three patrons at a bar in southwestern Montana, authorities said. Michael Paul Brown allegedly opened fire around 10:30 a.m. local time Friday at The Owl Bar in Anaconda, a city of about 9,000 people in southwestern Montana, according to the Montana Department of Justice.

Law enforcement officers are scouring a mountainous area of western Montana for a military veteran who authorities say opened fire at a bar, killing four people