Clash by Night (1964)

"Clash by Night" is a 1964 Crime movie directed by Montgomery Tully and starring by Terence Longdon, Jennifer Jayne. A gangster is caught and arrested by police. When he's being transported by bus -- filled with innocent civilians -- it's hi-jacked by his gang in attempt to free their boss. They hide out. As the authorities close in they threaten to torch the barn the escapee and his men are hiding in -- with their hostage inside.