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.

Those killed on Friday were a bartender and three patrons, ranging in age from 59 to 74, the authorities said. The suspect fled into the nearby foothills.

Montana Division of Criminal Investigation administrator Lee Johnson says 45-year-old Michael Paul Brown fled The Owl Bar after the Friday shooting in the small town of Anaconda.